Text

2020 Annual Radiological Environmental Operating Report
	ML21120A228
Person / Time
Site:	Seabrook
Issue date:	04/30/2021
From:	Levander M; NextEra Energy Seabrook
To:	; Document Control Desk, Office of Nuclear Reactor Regulation
References
	SBK-L-21044
	Download: ML21120A228 (280)
	v • d • e

NEXTera ENERGY e SEABROOK April 30, 2021 Docket No. 50-443 SBK-L-21044 U. S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, D.C. 20555-0001 Seabrook Station 2020 Annual Radiological Environmental Operating Report Pursuant to the requirements of 10 CFR 50.36a(a)(2) and Seabrook Station Technical Specification 6.8.1.3, NextEra Energy Seabrook, LLC submits the 2020 Annual Radiological Environmental Operating Report. The report smnmarizes the implementation of the NextEra Energy Seabrook, LLC Radiological Environmental Monitoring Program (REMP). Attachment 1 to the report is the complete data set for the REMP samples.

A copy of this report is also being provided to the Commonwealth of Massachusetts, Department of Public Health; and the State of New Hampshire, Bureau of Radiological Health.

Should you require further information regarding this matter, please contact David Robinson, Chemistry and Radiation Protection Department Manager, at (603) 773-7496.

Sincerely, NextEra Energy Seabrook, LLC

/UA/G Matthew Levander Licensing Manager NextEra Energy Seabrook, LLC PO Box 300, Seabrook, NH 03874

U. S. Nuclear Regulatory Commission SBK-L-21044/ Page 2 cc: with enclosure NRC Region I Administrator NRC Project Manager, Project Directorate I-2 NRC Senior Resident Inspector S. Wilson, Region I Inspector NH DHHS Office of Community & Public Health Bureau of Radiological Health 29 Hazen Drive Concord, NH 03301-6527 Massachusetts Department of Public Health Radiation Control Program Schraff! Center, Suite 1M2A 529 Main Street Charlestown, MA 02129 NH Fish & Game Department Cheri Patterson, Marine Division Chief 225 Main Street Durham NH 03824 NH Department of Environmental Services Thomas E. O'Donovan, Director Water Division 29 Hazen Drive; PO Box 95 Concord, NH 03302-0095 US Environmental Protection Agency Region 1 5 Post Office Square Suite 100 Boston, MA 02109-3946 Watershed Management Bureau Chris Nash, Shellfish Program Manager Water Division, NH Department of Environmental Services 222 International Drive, Suite 175 Portsmouth, NH 03801

NEXTera' EN:?~~,

2020 Annual Radiological Environmental Operating Report April 2021

SE°ABR.OQK STATION ANNUAL RADIOLOGICAL ENVIRONMENTAL OPERATlt'JG REPORT For the Period . '**."

January - Decemb~r 2020

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Docket No. *50-443.

Prepared By:

NextEra Energy Seabrook, LLC Chemistry Department * .

Seabrook Station

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Framato{tle Inc.

Materials and F.luence Group

Lynchburg, VA 24506

Prepared *By: ~<" d,, 1!J .RAW.!V°. * : Date:

The.adore A. Messler - Framatome Inc.

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Date:

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Andreas Glotas, NextEra Energy Seabrook, LLC . :' *: :;~

. .J Approved By. aL,z{ a ~

David Rob[nson, NextEra Energy Seabrook, LLC 0a"'

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SEABROOK STATION ANNUAL RADIOLOGICAL ENVIRONMENTAL OPERATING REPORT For the Period January - December 2020 April 2021 Docket No. 50-443 Prepared By:

NextEra Energy Seabrook, LLC Chemistry Department Seabrook Station And Framatome Inc.

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TABLE OF CONTENTS EXECUTIVE

SUMMARY

............................................................................................................................................................ IV LIST OF TABLES ........................................................................................................................................................................ VII LIST OF FIGURES .................................................................................................................................................................... VIII

1.0 INTRODUCTION

.................................................................................................................................................................. 1 2.0 PLANT OPERATIONS ENVIRONMENTAL MONITORING PROGRAM .................................................................. 2 3.0

SUMMARY

OF PLANT OPERATIONS RADIOLOGICAL ENVIRONMENTAL MONITORING DATA ............ 13 3.1 AIR PARTICULATE ............................................................................................................................................................... 14 3.2 CHARCOAL FILTERS ............................................................................................................................................................. 23 3.3 MILK .................................................................................................................................................................................... 26 3.4 SURFACE WATER ................................................................................................................................................................. 32 3.5 GROUND WATER ................................................................................................................................................................. 36 3.6 SEDIMENT ............................................................................................................................................................................ 42 3.7 FISH ..................................................................................................................................................................................... 46 3.8 LOBSTERS ............................................................................................................................................................................ 50 3.9 SHELLFISH ........................................................................................................................................................................... 54 3.10 IRISH Moss .......................................................................................................................................................................... 59 3.11 FOOD CROP .......................................................................................................................................................................... 63 3.12 VEGETATION ........................................................................................................................................................................ 66 3.13 DIRECT RADIATION ............................................................................................................................................................. 69 4.0 DRY FUEL STORAGE REMP & DATA

SUMMARY

.................................................................................................... 95 4.1 DIRECT RADIATION FROM DFS ............................................................................................................................................ 95 5.0 PROGRAM DEVIATIONS AND REPORTING ............................................................................................................ 108 5 .1 SAMPLING PROGRAM DEVIATIONS .................................................................................................................................... 108 5 .2 COMPARISON OF ACHIEVED LLDS WITH REQUIREMENTS ................................................................................................. 108 5.3 COMPARISON OF RESULTS AGAINST REPORTING LEVELS .................................................................................................. 109 6.0 QUALITY ASSURANCE PROGRAM ............................................................................................................................ 112 6.1 GEL LABORATORIES QA ................................................................................................................................................... 112 6.2 ENVIRONMENTAL TLD QA ............................................................................................................................................... 146 7.0 LAND USE CENSUS ......................................................................................................................................................... 149 ATTACHMENT 1: SAMPLE ANALYSIS DATA LIST FOR 2020 ....................................................................................... 151 iii

Executive Summary Both the plant operations and Dry Fuel Storage Radiological Environmental Monitoring Programs (REMP) for Seabrook Station operated successfully for the period of January through December 2020. This report describes the REMP and its implementation as required by Technical Specifications and as defined in the Offsite Dose Calculation Manual (ODCM). It also contains analytical results, data evaluation, dose assessment (as needed), and data trends for each environmental sample medium. Also included are the results of the Land Use Census, historical data, and the environmental laboratory performance in the Quality Assurance Inter-comparison Program required by the ODCM.

Radioactivity levels in the vicinity of Seabrook Station from January 1 through December 31, 2020 in air, water, sediment, milk, fish, food crops, and vegetation, as well as direct radiation measurements have been analyzed, evaluated, and summarized. The results of the REMP are intended to supplement the results of the radiological effluent monitoring by verifying that any measurable concentration of radioactive materials and levels of radiation are not higher than expected on the basis of the effluent measurement and modeling of the environmental exposure pathways.

Radiation and radioactivity in the environment is monitored within a 10-mile radius of the site. Two types of samples are taken. The first type, control samples, is collected from areas that are beyond measurable influence of Seabrook Station. These samples are used as reference data. Normal background radiation levels, or radiation present due to causes other than Seabrook Station, can thus be compared to the environment surrounding the nuclear power station. Indicator samples are the second sample type obtained.

These samples show how much measureable radiation or radioactivity (if any) is contributed to the environment by the site. Indicator samples are taken from areas close to the station where any plant contribution will be at the highest potential concentration. The ODCM minimum required plant operations REMP included the collection for 2020 of at least 576 samples, with a total of 2416 individual measurement analyses. In 2020, the total number of sample analysis sets (both required and non-required) equaled 827 taken from 98 locations around Seabrook Station. These were collected from aquatic, atmospheric, and terrestrial environments. An estimated 5095 individual measurement analyses were performed on these samples. The plant operations radiological environmental monitoring program is outlined in Table 2.0-1.

Radiation environmental monitoring associated with Dry Fuel Storage (DFS) in 2020 included an additional 19 TLD direct radiation measurements beyond those listed as being part of the REMP. The DFS environmental monitoring program is shown on Table 4.0-1.

Prior to station operation, samples were collected and analyzed to determine the amount of radioactivity present in the area. The resulting values are used as a "pre-operational baseline." Current analysis results from the indicator samples are compared to both current control sample values and the pre-operational baseline to determine if changes in radioactivity levels are attributable to station operations.

A report is required to be submitted to the Nuclear Regulatory Commission when the level of radioactivity as a result of plant operations in an environmental sampling medium at a specified location exceeds the reporting level limits specified in the ODCM when averaged over any calendar quarter. Also, when more than one of the radionuclides is detected in the sampling medium, this report shall be submitted if:

Concentration (1) +Concentration (2) + ... ;:: 1.0 Limit Level ( 1) Limit Level (2)

Based on the analytical results of environmental samples during 2020, Seabrook Station reporting levels were not exceeded.

All off-site radioactivity detected was attributable to either naturally-occurring radionuclides, previous nuclear weapons tests, the Fukushima Daiichi nuclear accident in Japan on March 11, 2011, or other man-made sources.

In 2020, the maximum whole body dose to the hypothetically exposed individual due to Seabrook Station effluents and operations was estimated to be 0.0809 mrem. This whole body dose is the sum of all the exposure pathways for liquid and gaseous effluents, plus the direct whole body dose from station sources.

This total represents approximately 0.324% of the whole body dose limits for a member of the public as set forth in 40CFR190.

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The average effective dose per individual in the U.S. population from ubiquitous or background radiation sources is about 3.11 mSv/yr (311 mrem/yr), with another 3.00 mSv/yr (300 mrem/yr) resulting from medical procedures and imaging (NCRP Report No. 160, "Ionizing Radiation Exposure of the Population of the United States" (2009)). The estimate for natural background includes radon gas which has always been present but has not always been included in previous estimates. In some regions of the country, the amount of natural radiation is significantly higher. Residents of Colorado, for example, receive an additional 60 mrem/yr due to the increase in cosmic and terrestrial radiation levels. In fact, for every 100 feet above sea level, a person will receive an additional 1 mrem/yr from cosmic radiation. In several regions of the world, naturally high concentrations of uranium and radium deposits result in doses of several thousand mrem/yr to their residents (CRC Handbook. "Radioecology: Nuclear Energy and the Environment", F. Ward Whicker and Vincent Schultz, Volume I, 1982).

Analytical results are divided into four categories based on exposure pathways: Airborne, direct radiation, ingestion, and waterborne. Each of these pathways is described below:

The airborne exposure pathway includes airborne iodine and airborne particulate. The 2020 results were similar to previous years, excluding the Fukushima Daiichi event in 2011. There was no notable increase in natural products and no detectable fission products or other plant-related radionuclides in the airborne particulate media during the year.

The direct exposure pathway measures environmental radiation exposures by use of thermoluminescent dosimeters (TLDs). TLD results have indicated a trend that compares with previous years which reflect the natural variability of background radiation from one location to another. The exposure rate response at some individual monitoring stations has exhibited step changes at some point in the past that appear to be related to changes in local conditions in the area of the dosimeter measurement. These step observations have been noted at various locations (both control and indicator stations) with no correlation with distance from Seabrook Station, leading to the conclusion that the changes in local TLD responses are not related to Seabrook operations. As a result, no detectable radiation contribution from Seabrook Station sources was identified via TLD environmental measurements off-site during the course of 2020 from either plant operations or from the spent fuel in the Dry Fuel Storage Facility.

The ingestion exposure pathway includes milk, fish, shellfish, terrestrial food products and leafy vegetation samples. The gamma spectroscopy analyses indicated the most prominent positive results were for potassium-40 (K-40) at average environmental levels. Other naturally-occurring radionuclides were also periodically detected. However, past world-wide nuclear events such as atmospheric testing of nuclear weapons and the Fukushima Daiichi nuclear accident did result in detectable fallout of fission related radioactivity (Cs-137) in milk. Neither fish, shellfish, nor terrestrial food products (strawberries, blueberries and tomatoes) had any detectable fission product related radioactivity. No radionuclides related to plant effluents were detected in any of these sample media during 2020. For the one fission product (Cs-137) detected in milk, the concentration falls within the range of past and pre-operational measurements and can be attributed to past weapons testing fallout.

The waterborne exposure pathway includes surface (ocean) water, drinking water supply, shallow well water, sea algae (Irish Moss) and sediment. Water samples were analyzed for tritium, gross-beta and gamma-emitting radionuclides. Irish Moss was analyzed for gamma-emitting radionuclides.

Tritium was not identified in the water samples analyzed. For groundwater, the gross beta activity detected at all locations is similar to what was detected in the pre-operational program and is consistent with results from previous years of commercial operations. Gamma analysis of samples indicated no plant-related gamma-emitting radionuclides above detection limits.

The results of the 2020 REMP continue to clearly demonstrate that there is no significant short term or chronic long-term radiological impact on the environment in the vicinity of Seabrook Station from plant operations and that there is no detectable impact to members of the public associated with the DFS facility.

The REMP monitoring did detect local area fallout related to past global nuclear events, such as atmospheric weapons testing and the Japanese nuclear accident in March 2011, thereby demonstrating the sensitivity and capability of the REMP to detect low level radiological changes in the environment and the likely source. The v

REMP confirmed that plant effluents in 2020 did not contribute measurable radiation exposure to the general public. This finding is consistent with previous years' monitoring conclusions. As a result, no increasing or changing trends in plant related radiological impacts on the environment are found.

vi

LIST OF TABLES Number Title Page 2.0-1 Plant Operations Radiological Environmental Monitoring Program................................. . 3 2.0-2 Plant Operations Radiological Environmental Monitoring Locations............................... 4

3. 1-1 REMP Summary (Medium: Air Particulates)............ .. .. .. .. .. .. .. .. .. .. .. .. .. . .. .. .. .. .. .. . .. .. . 21 3.2-1 REMP Summary (Medium: Charcoal Cartridge)................................................. . 24 3.3-1 REMP Summary (Medium: Milk) .. .. .. .. .. .. ... .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. . .. .. .. . .. .. .. .. 30 3.4-1 REMP Summary (Medium: Sea Water).............................................................. 33 3.5-1 REMP Summary (Medium: Ground Water) .. .. .. .. .. .. .. . .. .. .. .. . .. . .. .. .. . .. .. . .. .. .. .. .. .. . .. . .. 39 3.6-1 REMP Summary (Medium: Sediment) .. . . .. . .. .. . . .. . .. . .. .. . .. . .. . .. . . .. .. . . .. . .. .. . .. . .. . .. . .. . .. .. 43 3.7-1 REMP Summary (Medium: Fish) .. .. .. .. .. .. .. .. . .. .. .. . .. . .. .. .. .. .. .. .. .. .. . .. .. . .. .. .. .. .. .. .. .. .. . 47 3.8-1 REMP Summary (Medium: American Lobster) .. . .. . .. . . .. . .. .. . .. . . .. .. . .. . .. . .. . .. . . .. .. . ... .. . . 51 3.9-1 REMP Summary (Medium: Mussel Body) .. .. .. .. .. .. . .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. . .. .. .. .. . .. .. 55 3.9-2 REMP Summary (Medium: Mussel Shell)........................................................... 58

3. 10-1 REMP Summary (Medium: Irish Moss).............................................................. 60

3. 11-1 REMP Summary (Medium: Food Crops)............................................................. 64

3. 12-1 REMP Summary (Medium: Vegetation).............................................................. 67 3.13-1 Environmental TLD Measurements.................................................................................. 71

3. 13-2 Pre-Operational Environmental TLD Measurements .. .. .. .. .. .. . .. .. .. .. . .. .. .. .. .. . .. .. .. .. .. .. 73

3. 13-3 Facility Related Dose using ANSl/HPS N13.37-2014 Methodology................................ 74 4.0-1 Dry Fuel Storage (DFS) TLD Monitoring Locations................................................ 98 4.1-1 DFS Environmental TLD Measurements (2020)... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... .... 99

4. 1-2 DFS Facility Related Dose using ANSl/HPS N13.37-2014 Methodology..................... 100 5.2-1 Detection Capabilities for Environmental Sample Analysis.. ....................... .................... 110 5.3-1 Reporting Levels for Radioactivity Concentrations in Environmental Samples............... 111

6. 1-1 2020 Inter-Lab Radiological Proficiency Testing Results and Acceptance Criteria......... 118 6.1-2 2020 Eckert & Ziegler Analytics Performance Evaluation Results .................................. 130 6.1-3 REMP Intra-Laboratory Data Summary: Bias & Precision by Matrix .......................... 133 6.1-4 All Radiological Intra-Lab Data Summary: Bias and Precision Matrix . .. .. .. .. .. .. .. . .. .. .. .. . 135

6. 1-5 2020 Corrective Action Report Summary . .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. . .. .. . .. .. .. .. .. .. .. .. .. .. .. 142 6.2-1 Percentage of Individual Dosimeters That Passed EDC Internal Criteria .. .. .. .. . .. .. .. .. .. 146 6.2-2 Mean Dosimeter Analyses (N=6) ........................................................................ 147 6.2-3 Summary of Independent Dosimeter Blind Spike Testing .. .. .. .. .. .. .. . .. . .. .. .. .. .. .. .. .. .. . .. 14 7 6.2-4 Summary of Independent Blind Duplicate Dosimeter Testing .. .. . .. .. .. .. .. .. .. .. .. .. .. .. .. .. . 148

7. 0-1 2020 Land Use Census Resu Its ......................................................................... 150 vii

LIST OF FIGURES Number Figure 2.1 Radiological Environmental Monitoring Locations within 4 Km of Seabrook Station........................................... 7 Figure 2.2 Radiological Environmental Monitoring Locations Between 4 & 12 Km of Seabrook Station... . . . . . . . . . . . . . . . . . . .. . .. . .. . . . 8 Figure 2.3 Radiological Environmental Monitoring Locations Outside 12 Km of Seabrook Station...................................... 9 Figure 2.4 Direct Radiation Monitoring Locations Within 4 Km of Seabrook Station... . . . . . . . . . . . . . .. .. . . . . .. . . . . . .. . . . . . . . . . . . . .. . .......... .. .. . . . . 10 Figure 2.5 Direct Radiation Monitoring Locations Between 4 & 12 Km of Seabrook Station... . . . . . . . . . . . . . . . . .. . .. . . . .. . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . .. .. . 11 Figure 2.6 Direction Radiation Monitoring Locations Outside 12 Km of Seabrook Station... . . . . . . . . . . .. .. . . . . . .. . . . . . . . . . . . . . .. . . . .. . . . . .. . . . . . . . . . . . . . 12 Figure 3.1 Gross-Beta Measurements of Air Particulate Filters............................... 16 Figure 3.1.1 Gross-Beta Measurements of Air Particulate Filters Quarterly Averages......................................................................... 17 Figure 3.1.2 Gross-Beta Measurements of Air Particulate Filters Quarterly Averages......................................................................... 18 Figure 3.1.3 Gross-Beta Measurements of Air Particulate Filters Quarterly Averages......................................................................... 19 Figure 3.1.4 Gross-Beta on Air Particulate Filters Quarterly Averages........................ 20 Figure 3.2 1-131 Measurements of Air Charcoal Cartridges.................................. 25 Figure 3.3 Cesium-137 in Milk........................................................................ 27 Figure 3.3.1 Cesium-137 in Milk Annual Average Concentrations............................ 28 Figure 3.3.2 Cesium-137 in Milk Annual Average Concentrations............................. 29 Figure 3.5 Gross-Beta Measurements of Ground Water....................................... 37 Figure 3.5.1 Gross-Beta Measurements of Ground Water Semi-Annual Averages....................................................................... 38 Figure 3.6 Environmental Radiation Measurements (Using TLDs)... ... . .. ... ... ... ............. 77 Figure 3.6.1 Environmental Radiation Measurements (Using TLDs)...... ... ... .. . . .. ... ... ... ... 78 Figure 3.7 Environmental Radiation Measurements (Using TLDs).... .. .. . ... ... ... ... ... . . . . . 79 Figure 3.7.1 Environmental Radiation Measurements (Using TLDs). .. ... .. . ... ... ...... ... .. . . . 80 Figure 3.8 Environmental Radiation Measurements (Using TLDs)... .. . ... . .. ... .... ... ... . . . .. 81 Figure 3.8.1 Environmental Radiation Measurements (Using TLDs)... ... ... ... . .. ... .............. 82 Figure 3.9 Environmental Radiation Measurements (Using TLDs).... .. ... ... ... . . . ... ... . .. ... 83 Figure 3.9.1 Environmental Radiation Measurements (Using TLDs).... .. ... . . . ... ... .. . ... . .. ... 84 Figure 3.10 Environmental Radiation Measurements (Using TLDs). .. ... ... .. . .. . ... .. . ... ... .. . 85 Figure 3.10.1 Environmental Radiation Measurements (Using TLDs).............................. 86 viii

LIST OF FIGURES (Continued)

Figure 3.11 Environmental Radiation Measurements (Using TLDs)... ... ... ... ... ... ... ... ..... 87 Figure 3.11.1 Environmental Radiation Measurements (Using TLDs)... ... ... ... ... ... ... ... ..... 88 Figure 3.12 Environmental Radiation Measurements (Using TLDs)... ... ... ... ... ... ... ..... ... 89 Figure 3.12.1 Environmental Radiation Measurements (Using TLDs)...... ...... ...... ........ ... 90 Figure 3.13 Environmental Radiation Measurements (Using TLDs).................... .... .. .. . 91 Figure 3.13.1 Environmental Radiation Measurements (Using TLDs)...... ...... ...... ........ ... 92 Figure 3.14 Environmental Radiation Measurements (Using TLDs)... ... ...... ...... ...... ..... 93 Figure 3.14.1 Environmental Radiation Measurements (Using TLDs)...... ...... ...... ........ ... 94 Figure 4.0.1 Dry Fuel Storage TLD Environmental Monitoring Locations . . . . . . . . . . . . . . . . .. . . . . 97 Figure 4.1 -DFS Control Radiation Measurements (Using TLDs) ................................. 102 Figure 4.2 DFS Environmental Radiation Measurements (Using TLDs)...... ...... ...... .... 103 Figure 4.3 DFS Environmental Radiation Measurements (Using TLDs)...... ...... ...... ... 104 Figure 4.4 DFS Environmental Radiation Measurements (Using TLDs)...... ...... ...... ... 105 Figure 4.5 DFS Environmental Radiation Measurements (Using TLDs)... ... ... ... ... ... ... 106 Figure 4.6 DFS Environmental Radiation Measurements (Using TLDs)...... ...... ...... ... 107 ix

ANNUAL RADIOLOGICAL ENVIRONMENTAL OPERATING REPORT 1.0 Introduction NextEra Energy Seabrook, LLC's Radiological Environmental Monitoring Program (REMP) consists of two interconnected sample collection and measurement schedules that look for environmental influences from: (1) plant operations which release to the environment radioactive materials in liquid and gaseous effluents, and direct radiation from plant facilities inside the power block Protected Area, and (2) direct radiation from used fuel placed in the Dry Fuel Storage (DFS) facility located in the West Southwest sector approximately 0.38 miles from the Containment Building. Several monitoring locations provide data that are shared or used in the assessment of both plant and DFS operations.

The plant operations REMP at Seabrook Station has been designed and carried out to achieve the following specific objectives:

To provide an indication of the appearance or accumulation of any radioactive material in the environment caused by the operation of the nuclear power station.

To provide assurance to regulatory agencies and the public that the station's environmental impact is known and within anticipated limits.

To verify the adequacy and proper functioning of station effluent controls and monitoring systems.

To provide standby monitoring capability for rapid assessment of risk to the general public in the event of unanticipated or accidental releases of radioactive material.

In July 2008, the plant operations REMP was supplemented with the DFS environmental monitoring for direct radiation when used nuclear fuel assemblies were for the first time transferred to the on-site DFS facility located WSW of the power block.

NextEra Energy Seabrook, LLC staff collected the terrestrial samples. Normandeau Associates, Inc.

collected the marine and sediment samples. After initial sample preparation for shipment, the samples were sent to GEL Laboratories, Inc. of Charleston, SC for analysis. The Environmental Dosimetry Company located in Sterling, MA processed the environmental TLDs for the entire year.

This report is a summary of the findings of the REMP for 2020. It is being provided in compliance with Part A of Seabrook Station's ODCM and Technical Specification 6.8.1.3.

2.0 Plant Operations Environmental Monitoring Program Table 2.0-1 outlines the plant operations monitoring program as specified in the Seabrook Station ODCM, Part B, Section 4. Table 2.0-2 lists the operational sampling stations and their specific locations (distances are measured from the center of the Unit 1 Containment Building). The sampling locations are shown on maps in Figures 2.1 through 2.6. The sampling and analysis program as described above fulfills the minimum requirements for environmental sample collection and analysis as contained in ODCM Table A.9.1-1, and includes additional sampling of various pathways and locations beyond the minimum requirements.

Below are listed the two-letter media codes and what they represent:

AP Air Particulate CF Charcoal Filter TM Milk WG Ground Water WS Surface (Sea) Water SE Sediment FH Fish HA Lobsters MU Mussels (Shellfish - edible portion only)

MS Mussels (Shellfish - shell portion only)

TL Direct Radiation (TLD)

AL Irish Moss (algae)

TF Food Crop TG Vegetation (broad-leaf)

Table 2.0-1 Plant Operations Radiological Environmental Monitoring Program Media Sampling Frequency Required Analyses Air Particulate (AP) -Bi-Weekly Gross Beta

-Quarterly Composite Gamma spectroscopy Charcoal Filter (CF) -Bi-Weekly 1-131 Milk (TM) -Monthly (Semimonthly Gamma spectroscopy when animals 1-131 are on pasture)

Surface (Sea) Water (WS) -Monthly Gamma spectroscopy

-Quarterly Composite H-3 (composite)

Sediment (SE) -Semiannually Gamma spectroscopy Fish & Invertebrates -Quarterly or Gamma spectroscopy (FH, HA, MU) -Semiannually Direct Radiation (TL) -Quarterly Integrated gamma exposure Irish Moss (AL) -Semiannually Gamma spectroscopy Ground Water (WG) -Quarterly Gamma spectroscopy Gross Beta H-3 Food Crops (TF) -Monthly/Growing Season Gamma spectroscopy Vegetation (TG) -Monthly/Growing Season Gamma spectroscopy 1-131

Note that broad leaf vegetation is substituted for milk due to insufficient number of required milk sampling locations in the site area.

Table 2.0-2 Plant 0Qerations Radiological Environmental Monitoring Locations<a) (b) 2020 Approx.

Distance From Direction Station Code Station Plant From (Media - Sta. No.) DescriQtion Zone (km) Plant AP/CF-01+ PSNH Barge Landing Area 1 2.6 ESE AP/CF-02+ Hampton Marina (Harbor Rd) 1 2.5 E AP/CF-03+ Southwest Boundary (Rock Pile) 1 1.0 SW AP/CF-04+ West Boundary (Plate Yard) 1 1.2 w AP/CF-05 Winnacunnet High School 1 4.0 NNE AP/CF-07+ PSNH Substation 1 5.7 NNW AP/CF-08 E&H Substation 1 3.4 SSE AP/CF-09+ Georgetown Electric Light Co. 2 21.4 SSW TM-15 Hampton Falls, NH 6.9 NW WG-01 Seabrook Town Wells 1 5.6 w WG-13 Seabrook Station Well No. 13 1 1.0 N WG-14 Brimmer's Lane 1 1.3 NNW WS-01+ Hampton-Discharge Area 1 5. 1 E WS-51+ Ipswich Bay 2 26.2 SSE WS-10

Seabrook Marsh 1 0. 18 SSE SE-02 Hampton-Discharge Area 1 5.2 E SE-07 Hampton Beach 1 3.3 E SE-08+ Seabrook Beach 1 3.3 ESE SE-52 Ipswich Bay 2 26.2 SSE SE-57 Plum Island Beach 2 22.4 SSE FH-03+ Hampton-Discharge Area 1 5.0 ESE FH-53+ Ipswich Bay 2 23.3 SSE FH-06 Hampton-Discharge Area 1 5.2 E HA-04+ Hampton-Discharge Area 1 5. 1 E HA-54+ Ipswich Bay 2 27.9 SSE MU-06+ Hampton-Discharge Area 1 5.2 E MU-09 Hampton Harbor 1 2.5 E MU-56+ Ipswich Bay 2 28.6 SSE MU-59 Plum Island 2 22.0 SSE MS-06 Hampton-Discharge Area 1 5.2 E MS-56 Ipswich Bay 2 28.6 SSE AL-05 Hampton-Discharge Area 1 5.2 E AL-55 Ipswich Bay 2 28.7 SSE TF-02 Hampton Falls, NH 1 5.0 WNW TF-03 Salisbury, MA 1 5. 1 SW TF-06 Ipswich, MA 2 26.0 s Table 2.0-2 (Cont'd)

Plant 012erations Radiological Environmental Monitoring Locations(a) (b) 2020 Approx.

Distance From Direction Station Code Station Plant From (Media - Sta. No.) Descri12tion Zone (km) Plant TG-08+ North Access Rd, Site Boundary 1 1.05 w TG-09+ General Office Bid. Site Boundary 1 0.97 SW TG-10+ Georgetown Electric Light Co. 2 21.4 SSW TL-01+ Brimmer's Lane, Hampton Falls 0.97 N TL-02+ Landing Road, Hampton 3.0 NNE TL-03+ Glade Path, Hampton Beach 2.9 NE TL-04+ Island Path, Hampton Beach 2.3 ENE TL-05+ Harbor Road, Hampton Beach 2.5 E TL-06+ PSNH Barge Landing Area 2.7 ESE TL-07+ Cross Road, Seabrook Beach 2.6 SE TL-08+ Farm Lane, Seabrook 1.3 SSE TL-09+ Farm Lane, Seabrook 1.3 s TL-10+ Site Boundary Fence 1.1 SSW TL-11+ Site Boundary Fence 1.0 SW TL-12+ Site Boundary Fence 1.2 WSW TL-13+ Inside Site Boundary 1.2 w TL-14+ Trailer Park, Seabrook 1.3 WNW TL-15+ Brimmer's Lane, 1.4 NW Hampton Falls TL-16+ Brimmer's Lane 1.2 NNW Hampton Falls TL-17+ South Road, North Hampton 0 7.8 N TL-18+ Mill Road, North Hampton 0 7.6 NNE TL-19+ Appledore Avenue, 0 7.7 NE North Hampton TL-20+ Ashworth Avenue, 0 3.2 ENE Hampton Beach TL-21+ Route 1A, Seabrook Beach 0 3.7 SE TL-22+ Cable Avenue, Salisbury 0 7.6 SSE Beach TL-23+ Ferry Road, Salisbury 0 8.1 s TL-24+ Ferry Lots Lane, 0 7.2 SSW Salisbury TL-25+ Elm Street, Amesbury 0 7.6 SW TL-26+ Route 107A, Amesbury 0 8.1 WSW TL-27+ Highland St. S. Hampton 0 7.5 w TL-28+ Rte. 150, Kensington 0 7.5 WNW TL-29+ Frying Pan Ln., Hampton Falls 0 7.2 NW TL-30+ Route 27, Hampton 0 7.6 NNW Table 2.0-2 (Cont'd)

Plant Operations Radiological Environmental Monitoring Locations(a) (bl 2020 Approx.

Distance From Direction Station Code Station Plant From (Media - Sta. No.) Description Zone (km) Plant TL-31+ Alumni Drive, Hampton s 3.8 NNE TL-32+ Seabrook Elementary School s 2.0 s TL-33+ Dock Area, Newburyport s 9.8 s TL-34+ Bow Street, Exeter s 12.0 NW TL-35+ Lincoln Ackerman School s 2.3 NNW TL-36+ Route 97, Georgetown 2 22.6 SSW TL-37+ Post Office Plaistow, NH 2 21.5 WSW TL-38+ Emerson St. Hampstead, NH 2 27.7 w TL-39+ Fremont, NH 2 27.0 WNW TL-40+ Newmarket, NH 2 21.6 NNW TL-41 Portsmouth, NH 2 21.0 NNE TL-42 Ipswich, MA 2 22.8 SSE TL-44 Education (Science & Nature) Center s 0.6 SW TL-45 Hampton Fire Station s 4.4 NE TL-46 Seabrook Beach (near Police Station) s 2.8 ESE TL-47 Hampton Falls, NH s 4.1 WNW Zone indices are: 1 = Indicator Stations; 2 =Control Stations; O =Outer Ring TLD; I = Inner Ring TLD; S = Special Interest TLD

+ = Sample Locations required by the Off-Site Dose Calculation Manual (ODCM)

Note that WS-10 is the same location as WS-02 reported in previous reports.

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-a 3.0 Summary of Plant Operations Radiological Environmental Monitoring Data The following pages summarize the analytical results of the plant operations environmental samples collected in 2020. Each environmental media category is presented as a separate subsection. A table that summarizes the data follows a discussion of the sampling requirements and results for each media type. Listed at the top of each table are the units of measurement for each medium. The left-hand column contains the radionuclide which is being reported, total number of analyses of that radionuclide, and the number of measurements that exceed the required reporting level as documented in Table A.9.1-3 of the ODCM. The latter are classified as "non-routine" measurements. The next column lists the Lower Limit of Detection (LLD) for those radionuclides that have detection capability requirements specified in the ODCM.

Those sampling stations which are adjacent to the plant and which could conceivably be affected by the operation of Seabrook Station are called "Indicator" or "Zone 1" stations. Distant stations, which are beyond potential plant influences, are called "Control" or "Zone 2" stations.

A set of statistical parameters is calculated for each radionuclide. This set of statistical parameters includes separate analyses for (1) the indicator stations, (2) the station having the highest annual mean concentration for that radionuclide, and (3) control stations. For each of the three groups of data, these parameters are as follows:

The mean value of all concentrations,

The range of values and

The number of positive measurements (a concentration which is greater than the MDC for the measurement) divided by the total number of measurements.

Each radioactivity measurement datum in this report is based on a single measurement and is reported as a concentration plus or minus a one standard deviation uncertainty. The quoted uncertainty term represents only the random uncertainty associated with the radioactive decay process (counting statistics), and not the propagation of all possible uncertainties in the analytical procedure. contains the data for the samples collected in 2020. The results are organized as follows:

(1) by sample type; (2) within each sample type the data are alphabetical by nuclide; and (3) within each radionuclide listing the data are chronologically arranged by end date (date of sample collection).

The radionuclide value concentrations have been corrected for radioactive decay. For composite samples, such as air particulates and airborne iodine, the GEL laboratory uses the mid-point of the collection period as the reference for decay correction until time of analysis.

3.1 Air Particulate Air monitoring stations were established at a total of eight locations, six locations required by the ODCM, Table A.9.1-1, and two additional sites included to supplement the program. Seven of the locations are indicators, while the remaining one is a control station located more than 21 km away from the plant.

Airborne particulates (AP) are collected by passing the air through a glass-fiber filter. In 2020, these filters were typically collected bi-weekly and held for a period (typically 100 hours0.00116 days 0.0278 hours 1.653439e-4 weeks 3.805e-5 months or more) before being analyzed for gross-beta activity (indicated as BETA in Table 3.1-1) to allow for the decay of Radon and Thoran daughter products. Continuous automated and real-time remote monitoring of vital air sampling system parameters is performed with telemetry that detects power outages, pump failures, filter degradation, tubing failures and excessive filter loading. The telemetry communicates by cellular transmission to a web server that communicates to a shift technician's pager when set-point thresholds are reached, providing 24/7 alert notification. This capability provides for timely identification of problems and corrective actions that reduce the potential loss of air sampling. If periods of high dust loading during the collection period cause a higher than normal differential pressure drop across the collection filters, the collection period may be reduced to weekly cycles to reduce the dust loading. There were no recorded collection cycle reductions due to dust loading in 2020. For the year, 208 particulate filters were collected and analyzed for gross beta activity.

The 2020 gross beta activity analyses for the indicator locations were found to be statistically equivalent to that seen at the control station (positive activity for all samples). The gross beta results are also similar to what was seen in the pre-operational program and for the last thirty years of commercial operation, with the exception of the Fukushima Daiichi related spike in 2011. All filter samples from all stations showed similar trends lines (see Figure 3.1) over the course of the year and from previous years (see Figures 3.1.1, 3.1.2, and 3.1.3). Figure 3.1.4 compares the quarterly average gross beta response of all indicator air sampling stations to the control location over the last 26 years, and shows no significant difference in the two data sets. It is also noted that no plant-related radionuclides (by gamma spectroscopy) were identified in any of the quarterly filter composite samples for 2020. The overall fluctuations at all stations seen in the gross beta activity throughout the year can be attributed to changes in environmental conditions unrelated to plant operations. Natural environmental processes such as wind direction, precipitation, snow cover, and soil temperature and moisture affect concentrations of naturally-occurring radionuclides in the atmosphere directly above land.

Gamma isotopic analyses of particulate filters are summarized on Table 3.1-1. The only radionuclides detected were naturally-occurring Be-7, which indicated positive in all air particulate samples, K-40 which was positive in one sample and Th-228, which was positive in one sample. Be-7 is of cosmogenic origin, and its presence is consistent with previous years in both the pre-operational and operational periods.

Near the end of 2010, analysis of environmental samples was changed from the AREVA Environmental Laboratory to GEL Laboratory after the AREVA lab discontinued operations. In comparing long term trends in gross beta activity, the results since 2011 appear to reflect a step increase at the time of the transition between labs. The reason for the step increase is related to the change in the gross beta counting equipment configurations and reference calibration standards used by the AREVA lab and GEL.

Both labs use(d) gas proportional counting of the filter element. However, AREVA applied a Cs-137 calibration source while the GEL lab uses a Tc-99 calibration source. In the case of the AREVA data record, the Cs-137 detection efficiency (typically 34%) was applied to the "gross" counts to determine the apparent activity. This inherently presumes that the radioactivity in a field sample is all Cs-137. In the case of the GEL data record, the Tc-99 efficiency (20.6%), is applied to the same "gross" counts as if all the radioactivity in this case is Tc-99. The end result is two different gross beta radioactivity determinations for the same level of environmental activity. In application, this is not an adverse condition in that the gross beta counting is used as a qualitative indicator of changes in environmental conditions, not as a quantitative measure of the actual radioactivity. Since the comparison of the response curves for each monitoring station, including the control station, are similar over time, the curves indicate that there is no detectable influence from a single nearby point source such as Seabrook Station.

The air particulate sampling program demonstrated no off-site dose to the public or impact to the environment from this pathway as the result of plant operations. This is consistent with previous years and the pre-operational program. The REMP Summary Table 3.1-1 lists the range of analysis results by radionuclide for Indicator and Control Stations for the air particulate environmental media. Attachment 1 to this report lists the individual analysis results for each measurement of air particulates under the Sample Type code AP.

Air particulate sample collection and analysis deviations from the ODCM required program (if any) are described in Section 5.

FIGURE 3.1 GROSS-BETA MEASUREMENTS OF AIR PARTICULATE FILTERS SEABROOK STATION 0.12 0.11 0.11 0.10 0.10 0.09 0.09 L...

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c.. 0.05 0.05 0.04 0.04 0.03 0.02 0.02 0.01 0.01 0.00 January February March April May June July August September October November December 2020

- AP-01 Barge Landing Area

- + - AP-02 Hampton Marina

-+-- AP-03 SW Boundary

- - AP-04 W Boundary AP-05 Winnacunnet High School

~ AP-09 Georgetown (Control)

- AP-07 PSNH Substation, Hampton

-+- AP-08 Exeter & Hampton Electric Co.

FIGURE 3.1.1 GROSS-BETA MEASUREMENTS OF AIR PARTICULATE FILTERS QUARTERLY AVERAGES SEABROOK STATION 0.16 i

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Fukushima-008 Daichii Event 5% Criticality March 2011 0.06 June, 1989 0.04 0.02 0 +-'-~~~--.--'-~-'------,~~~~~~~~~~~~~~~~~~~~~~~~~~~.--l--~~~~~~~~~~~~---,J 1986 1988 1990 1992 1994 1996 1998 2000 2002 2004 2006 2008 2010 2012 201 4 2016 2018 2020

<>-- AP-01 Barge Landing Area

--a- AP-02 Hampton Marina

-1r- AP-03 SW Boundary

- AP-06/09 Georgetown Substation (Control)

FIGURE 3.1.2 GROSS-BETA MEASUREMENTS OF AIR PARTICULATE FILTERS QUARTERLY AVERAGES SEABROOK STATION 0.16 Chernobyl 0.14 May, 1986 0.12 I

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1986 1988 1990 1992 1994 1996 1998 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020

-+-- AP-04 W Boundary

- a - AP-05 Vlllnnacunnet High School AP-06/09 Georgetown Substation (Control)

FIGURE 3.1 .3 GROSS-BETA MEASUREMENTS OF AIR PARTICULATE FILTERS QUARTERLY AVERAGES SEABROOK STATION 0.16 l Chernobyl

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--<>-- AP-06/09 Georgetown Substation (Control)

- e - AP-07 PSNH Substation, Hampton AP-08 Exeter & Hampton Electric Co.

FIGURE 3.1.4 GROSS-BETA ON AIR PARTICULATE FILTERS QUARTERLY AVERAGES SEABROOK STATION 0.08 - , - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - . - 0.08 Fukushima-0.06 Daichii Event 0.06 March 2011 Q)

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-o- Indicators

-o- Control Table 3.1-1 Radiological Environmental Program Summary Seabrook Nuclear Power Station, Seabrook, NH (January - December 2020)

MEDIUM: Air Particulates !AP) UNITS: pCi/cubic meter Indicator Stations Station With Highest Mean Control Stations Radionuclides Mean Station Mean Mean (No. Analyses) Required Range Range Range (Non-Routine*) LLD (No. Detected**) (No. Detected**) (No. Detected**)

BETA (208) 0.01 2.SE -2 08 2.7E -2 2.SE -2 (0) 8.5 - 57.4)E -3 1.1 - 4.9)E -2 1.3 - 4.9)E -2 (182/ 182) (26/ 26) (26/ 26)

Be-7 (32) 1.2E -1 01 1.3E -1 1.2E -1 (0) 9.0 - 14.7)E -2 1.1 - 1.4)E -1 8.6 - 15.3)E -2 (28/ 28) (4/ 4) (4/ 4)

K-40 (32) 1. lE -3 01 1.8E -3 6.8E -4 (0) -3.0 - 5.6)E -3 0.0 - 4.3)E -3 0.0 - 1.S)E -3 (1/ 28) (0/ 4) (0/ 4)

Cr-51 (32) -6.3E -5 02 l.6E -3 -3.8E -4 (0) -9.4 - 11. 6)E -3 -8.3 - ll.6)E -3 -6.6 - 2.9)E -3 (0/ 28) (0/ 4) (0/ 4)

Mn-54 (32) -2.8E -5 01 5.0E -5 O.OE 0 (0) -2.3 - l.3)E -4 -1.5 - 11.9)E -5 -1.7 - 2.0)E -4 (0/ 28) (0/ 4) (0/ 4)

Co-57 (32) O.OE 0 07 3.8E -5 2.9E -5 (0) -1.6 - l.O)E -4 -4.3 - 91.9)E -6 -1.2 - 7.0)E -5 (0/ 28) (0/ 4) (0/ 4)

Co-58 (32) 3.SE -5 03 1. 7E -4 -7.lE -5 (0) -2.3 - 4.0)E -4 7.6 - 24.0)E -5 -2.1 - 0.9)E -4 (0/ 28) (0/ 4) (0/ 4)

Fe-59 (32) 5.2E -5 01 2.2E -4 1. SE -4 (0) -1.2 - 1.4)E -3 -4.7 - 87.7)E -5 -4.4 - 10.0)E -4 (0/ 28) (0/ 4) (0/ 4)

Co-60 (32) 2.2E -5 04 9.9E -5 2.SE -5 (0) -2.2 - 1.9)E -4 3.6 - 15.8)E -5 -1.5 - 1.S)E -4 (0/ 28) (0/ 4) (0/ 4)

Zn-65 (32) -7.0E -5 05 1.2E -4 O.OE 0 (0) -6.9 - 4.3)E -4 -1.1 - 4.3)E -4 -3.2 - 2.6)E -4 (0/ 28) (0/ 4) (0/ 4)

Se-75 (32) 5.6E -5 02 1. 9E -4 O.OE 0 (0) -2.8 - 5.2)E -4 1.7 - 517.0)E -6 -1.2 - 1.l)E -4 (0/ 28) (0/ 4) (0/ 4)

Nb-95 (32) 6.8E -5 01 2.lE -4 -2.6E -5 (0) -5.9 - 4.7)E -4 -1.6 - 4.7)E -4 -2.9 - 3.3)E -4 (0/ 28) (0/ 4) (0/ 4)

Zr-95 (32) 7.6E -5 05 4.2E -4 O.OE 0 (0) -6.9 - 16.3)E -4 6.2 - 112.0)E -5 -1.1 - 1.6)E -4 (0/ 28) (0/ 4) (0/ 4)

Ru-103 (32) -3.4E -5 05 1.8E -4 -6.2E -5 (0) -5.0 - 7.3)E -4 -2.0 - 7.3)E -4 -3.9 - 2.8)E -4 (0/ 28) (0/ 4) (0/ 4)

Non-Routine refers to those radionuclides that exceeded the Reporting Levels in ODCM Table A.9.1-3.

- The fraction of detectable measurements (i.e .. > MDC with no uncertain identification) is shown in parentheses.

Table 3.1-1 (Continued)

Radiological Environmental Monitoring Program Summary Seabrook Nuclear Power Station, Seabrook, NH (January - December 2020)

MEDIUM: Air Particulates IAPl UNITS: pCi/cubic meter Indicator Stations Station With Highest Mean Control Stations Radionuclides Mean Station Mean Mean (No. Analyses) Required Range Range Range (Non-Routine*) LLD (No. Detected**) (No. Detected**) (No. Detected**)

Ru-106 (32) 5.6E -5 08 9.7E -4 -3.SE -4 (0) -1.9 - 2.4)E -3 -2.2 - 23.6)E -4 -8.8 - -0.8)E -4 (0/ 28) (0/ 4) (0/ 4)

Ag-108m (32) O.OE 0 02 8.lE -5 -1.4E -5 (0) -2.0 - 2.l)E -4 4.9 - 208.0)E -6 -7.8 - 4.7)E -5 (0/ 28) (0/ 4) (0/ 4)

Ag-110m (32) 2.8E -5 08 1.2E -4 -1. 9E -5 (0) -4.3 - 5.l)E -4 -1.3 - 3.8)E -4 -2. 6 - 1. 7) E -4 (0/ 28) (0/ 4) (0/ 4)

Sb-124 (32) -8.2E -5 09 3.6E -4 3.6E -4 (0) -1. 2 - 0. 9) E -3 2.6 - 5.S)E -4 2.6 - 5.S)E -4 (0/ 28) (0/ 4) (0/ 4)

Sb-125 (32) 3.lE -5 03 2.2E -4 2.SE -5 (0) -3.8 - 6.2)E -4 1.3 - 3.3)E -4 -2.2 - 1.7)E -4 (0/ 28) (0/ 4) (0/ 4) 1-131 (32) -4.7E -2 09 3.0E -3 3.0E -3 (0) -3.0 - 0.8)E -1 0.0 - 1.2)E -2 0.0 - 1.2)E -2 (0/ 28) (0/ 4) (0/ 4)

Cs-134 (32) 0.05 1. SE -5 03 8.4E -5 2.3E -5 (0) -2.5 - 2.3)E -4 -2.7 - 17.6)E -5 -6.9 - 16.3)E -5 (0/ 28) (0/ 4) (0/ 4)

Cs-137 (32) 0.06 -1. 7E -5 09 5.4E -5 5.4E -5 (0) -3.0 - 1.3)E -4 -3.2 - 16.6)E -5 -3.2 - 16.6)E -5 (0/ 28) (0/ 4) (0/ 4)

Ba-140 (32) 1. 9E -2 03 3.SE -2 -4.9E -3 (0) -3.7 - 11.l)E -2 1.6 - 5.S)E -2 -1. 6 - 1.S)E -2 (0/ 28) (0/ 4) (0/ 4)

La-140 (32) -7.2E -3 07 1. 7E -3 -3.9E -3 (0) -9.0 - 1.4)E -2 -4.4 - 14.3)E -3 -1.4 - 0.3)E -2 (0/ 28) (0/ 4) (0/ 4)

Ce-141 (32) 1.2E -5 03 5.lE -4 8.SE -5 (0) -1.1 - 1.8)E -3 1.4 - 12.S)E -4 -5. 7 - 11.8)E -4 (0/ 28) (0/ 4) (0/ 4)

Ce-144 (32) -4.4E -5 09 3.lE -4 3.lE -4 (0) -1. 0 - 0. 9) E -3 -3.9 - 8.0)E -4 -3.9 - 8.0)E -4 (0/ 28) (0/ 4) (0/ 4)

Ac-228 (32) 3.7E -4 02 1. lE -3 O.OE 0 (0) -1.2 - 1.8)E -3 5.4 - 18.2)E -4 -5.6 - 3.S)E -4 (0/ 28) (0/ 4) (0/ 4)

Th-228 (32) 1. 9E -4 02 5.lE -4 3.4E -4 (0) -1.1 - 6.2)E -4 3.1 - 6.2)E -4 -5.4 - 75.2)E -5 (0/ 28) (0/ 4) (1/ 4)

Non-Routine refers to those radionuclides that exceeded the Reporting Levels in ODCM Table A.9.1-3.

- The fraction of detectable measurements (i.e., > MDC with no uncertain identification) is shown in parentheses.

3.2 Charcoal Filters Charcoal filter (CF) cartridges are placed in series behind the air particulate glass-fiber filters at each of the air sampling locations. Monitoring stations were established at a total of eight locations. Seven of these are indicators and one is a control. Charcoal filters from the air sampling stations were collected and analyzed for 1-131 activity to a lower limit of detection (LLD) of 0.07 pCi/m 3 or lower.

During 2020, a total of 208 charcoal cartridges from eight locations were analyzed. As described for the air particulate samplers (see Section 3.1 ), the collection cycles for the charcoal filters were biweekly during 2020.

Off-normal conditions, such as observed high differential pressure across the associated particulate filter (none detected in 2020) which might be indicative of excessive dust loading, could prompt switching to a temporary weekly cycle (see Section 3.1).

No sample analyses indicated a detectable level for 1-131 that was statistically relevant (positive) at any of the air sampling locations during the year. Figure 3.2 shows the 1-131 measurement responses in 2020 for all air sampling stations. All analyses were below their respective measurement minimum detectable concentrations (MDC).

From initial criticality in June 1989 to the Fukushima Daiichi accident in March 2011, the Seabrook REMP program had not detected 1-131 at any offsite air sample locations. Following the March -April, 2011 air concentration spikes of 1-131 related to the Fukushima Daiichi accident releases, no detectable 1-131 has been observed. The pre-operational data for 1-131 are consistent with present (2020) data. Therefore, there are no increasing or decreasing trends related to Seabrook Station operations for airborne 1-131. The potential organ doses from 1-131 in gaseous effluents, if assumed to be released at the MDA, are well below the 10CFR50, Appendix I dose criteria.

The REMP Summary Table 3.2-1 list the range of analysis results for iodine (1-131) at both Indicator and Control Stations. Attachment 1 to this report lists the individual analysis results for each air sample measurement under the Sample Type code CF.

Charcoal filter sample collection and analysis deviations from the ODCM required program (if any) are described in Section 5.

Table 3.2-1 Radiological Environmental Monitoring Program Summary Seabrook Nuclear Power Station, Seabrook, NH (January - December 2020)

MEDIUM: Charcoal Cartridge !CF) UNITS: pCi/cubic meter Indicator Stations Station With Highest Mean Control Stations Radionuclides Mean Station Mean Mean (No. Analyses) Required Range Range Range (Non-Routine*) LLD (No. Detected**) (No. Detected**) (No. Detected**)

1-131 (208) 0.07 1. 9E -4 01 6.7E -4 6.6E -5 (0) -7.3 - 20.3)E -3 -7.3 - 20.3)E -3 -4.6 - 4.3)E -3 (0/ 182) (0/ 26) (0/ 26)

Non-Routine refers to those radionuclides that exceeded the Reporting Levels in ODCM Table A.9.1-3.

- The fraction of detectable measurements (i.e., >MDC with no uncertain identification) is shown in parentheses.

FIGURE 3.2 1-131 MEASUREMENTS OFAIR CHARCOALCARTRIDGES SEABROOK STATION 0.10 0.10 0.08 0.08 Al I data

<MDC 0.06 0.06

.....Cll Cll E 0.04 0.04 u

ti

I u

~

u a.

0.02 0.02 0.00

-0.02 -0.02

-0.04 -+----~-~--~--~--~--~--~--~-~--~--~--~ -0.04 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 2020

- CF-01 Barge Land in g Area - CF-02 Hampton Marina

---.- CF-03 SW Boundary - CF-04W Boundary

-+- CF-05 Winnacunriet High School - CF-08 Exeter & Hampton Electric Co.

-+-CF-09 Georgetown (Control) - cF-07 PSNH Substation, Hampton 3.3 Milk Milk samples (TM) were collected semi-monthly during the pasture season and monthly at other times. Samples are analyzed for low level 1-131 and gamma-emitting radionuclides.

The ODCM (Table A.9.1-1) requires that milk samples be collected from three locations within 5 km of the plant having the highest dose potential. If there are none, then one sample is required from milking animals in each of three areas between 5 to 8 km from the plant where the doses are calculated to be greater than 1 mrem/yr. Due to the limited inventory of milk animals in the site area, as reconfirmed by the 2020 Land Use Census, the number of available sample locations required by the ODCM sampling program could not be met (insufficient numbers of milk animals within 5 km, and only one milk location [designated TM-15] between 5 and 8 km). The ODCM allows for broad leaf vegetation samples to be collected if milk sampling cannot be performed in accordance to the REMP requirements. As a result, two site boundary locations and one control vegetation location are sampled to compensate for the limited milk availability (see Section 3.12).

A total of 18 milk samples were collected during the year from one available location. Each sample was analyzed for gamma emitting radionuclides. In addition, all samples were evaluated for low levels of 1-131 through an iodine extraction process. The gamma analyses on samples indicated that naturally-occurring K-40 was detectable in all milk samples. Also detected in 14 milk samples was Cs-137 at an average concentration of 8.8 pCi/kg (positive measurements only) which falls in the range of past and pre-operational measurements. The highest single Cs-137 analysis result in 2020 was 14.4 pCi/kg. Though the Fukushima Daiichi event in March 2011 may have contributed to the Cs-137 levels observed in milk in 2020, Cs-137 has historically been detected at similar levels in milk before the nuclear accident in Japan. Residual Cs-137 from past weapons testing fallout has been the major contributor attributed to the currently observed values in milk. Figures 3.3, 3.3.1 and 3.3.2 illustrate the analysis results (without regard to whether individual analysis indicated detectable or statistically not detectable concentrations) for Cs-137 in milk over the current period (2020) and previous years.

lodine-131 was not positively identified at any location for the year. This is consistent with previous years for both the pre-operational and operational phases of the program. Three samples did not meet the Lower Limit of Detection (LLD) requirements (1 pCi/kg) for 1-131 in milk (LSN's 519927001, 523902001, and 527400001). No increasing or decreasing trends in the radioactivity content of milk were observed.

The REMP Summary Table 3.3-1 lists the range of analysis results by radionuclide for the Indicator station (Historical Control Stations for the milk have ceased operations). Attachment 1 to this report lists the individual analysis results for each measurement of milk under the Sample Type code TM. Section 5 identifies deviations in the sample measurement program (if any), such as missed lower limits of detection (LLD) requirements.

FIGURE 3.3 CESIUM-137 IN MILK SEABROOK STATION 25 20 15 Cs-137 >MDC for all except Cl

..la::

0 rn 0..

5 0

-5 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 2020

-+- TM-15, Hampton Falls NH (Goats)

FIGURE 3.3.1 CESIUM-137 IN MILK ANNUAL AVERAGE CONCENTRATIONS 25 25 20 20 C ernobyl y, 198 Ol s

(_)

15 Fukushima- 15

a. Daichii Event SB 5% Criticality March 2011 June, 1989 SB Full Power 10 ~ May, 1990 10 5 5

--o- TM-04, Salisbury MA

--o-- TM-08 , Hampton Falls NH (prior to 1995 TM-10)

--o- TM-09, Hampton NH

- - TM-15, Hampton Falls NH FIGURE 3.3.2 CESIUM-137 IN MILK ANNUAL AVERAGE CONCENTRATIONS 30 Chernobyl May, 1986 25 25 SB 5% Criticality June , 1989 20 20 Fukushima-15 SB Full Power Daichii Event 15 Cl May, 1990 March 2011

~

G0..

10 10 5 5

-o- TM-16, Kensington NH

-fs- TM-21 , North Andover MA (Control)

- - TM-23 , Newbury, MA

- TM-24 , North Hampton NH

-O- TM-20, Rowley MA (Control)

Table 3.3-1 Radiological Environmental Monitoring Program Summary Seabrook Nuclear Power Station, Seabrook, NH (January - December 2020)

MEDIUM: Milk (TM) UNITS: pCi/kg Indicator Stations Station With Highest Mean Control Stations Radionuclides Mean Station Mean Mean (No. Analyses) Required Range Range Range (Non-Routine*) LLD (No. Detected**) (No. Detected**) (No. Detected**)

Be-7 (18) 2.2E 0 15 2.2E 0 NO DATA (0) -4.2 - 10.8)E 0 -4.2 - 10.8)E 0 (0/ 18) (0/ 18)

K-40 (18) 1.6E 3 15 1.6E 3 NO DATA (0) 1.4 - 1.7)E 3 1.4 - 1.7)E 3 (18/ 18) (18/ 18)

Cr-51 (18) 1. 4E -1 15 1.4E -1 NO DATA (0) -1.0 - 1.l)E 1 -1.0 - 1.l)E 1 (0/ 18) (0/ 18)

Mn-54 (18) 6.5E -3 15 6.5E -3 NO DATA (0) -1.4 - 0.8)E 0 -1. 4 - 0. 8) E 0 (0/ 18) (0/ 18)

Co-57 (18) 7.0E -3 15 7.0E -3 NO DATA (0) -1.1 - 1.0)E 0 -1.1 - 1.0)E 0 (0/ 18) (0/ 18)

Co-58 (18) -1.2E -1 15 -1.2E -1 NO DATA (0) -8.4 - 9.3)E -1 -8.4 - 9.3)E -1 (0/ 18) (0/ 18)

Fe-59 (18) -1. OE -2 15 -1.0E -2 NO DATA (0) -1.7 - 3.8)E 0 -1.7 - 3.8)E 0 (0/ 18) (0/ 18)

Co-60 (18) 3.4E -1 15 3.4E -1 NO DATA (0) -7.0 - 12.7)E -1 -7.0 - 12.7)E -1 (0/ 18) (0/ 18)

Zn-65 (18) -5.lE -2 15 -5.lE -2 NO DATA (0) -5.2 - 3.2)E 0 -5.2 - 3.2)E 0 (0/ 18) (0/ 18)

Se-75 (18) 2.0E -1 15 2.0E -1 NO DATA (0) -1.5 - 1.7)E 0 -1.5 - 1.7)E 0 (0/ 18) (0/ 18)

Nb-95 (18) 1.4E -1 15 1. 4E -1 NO DATA (0) -7.7 - 12.6)E -1 -7.7 - 12.6)E -1 (0/ 18) (0/ 18)

Zr-95 (18) -4.0E -1 15 -4.0E -1 NO DATA (0) -2.2 - 0.6)E 0 -2.2 - 0.6)E 0 (0/ 18) (0/ 18)

Ru-103 (18) -2.0E -1 15 -2.0E -1 NO DATA (0) -1.5 - 1.2)E 0 -1.5 - 1.2)E 0 (0/ 18) (0/ 18)

Ru-106 (18) 4.6E -1 15 4.6E -1 NO DATA (0) -8.6 - 13.9)E 0 -8.6 - 13.9)E 0 (0/ 18) (0/ 18)

Ag-108m (18) 3.0E -1 15 3.0E -1 NO DATA (0) -5.0 - 21.2)E -1 -5.0 - 21.2)E -1 (0/ 18) (0/ 18)

Non-Routine refers to those radionuclides that exceeded the Reporting Levels in ODCM Table A.9.1-3.

- The fraction of detectable measurements (i.e., > MDC with no uncertain identification) is shown in parentheses.

Table 3.3-1 (Continued)

Radiological Environmental Monitoring Program Summary Seabrook Nuclear Power Station, Seabrook, NH (January - December 2020)

MEDIUM: Milk (TM} UNITS: 12Ci/kg Indicator Stations Station With Highest Mean Control Stations Radionuclides Mean Station Mean Mean (No. Analyses) Required Range Range Range (Non-Routine*) LLD (No. Detected**) (No. Detected**) (No. Detected**)

Ag-110m (18) -2.SE -1 15 -2.SE -1 NO DATA (0) -2.3 - 1.S)E 0 -2.3 - 1.S)E 0 (0/ 18) (0/ 18)

Sb-124 (18) -1. 9E -1 15 -1. 9E -1 NO DATA (0) -2.0 - 2.0)E 0 -2.0 - 2.0)E 0 (0/ 18) (0/ 18)

Sb-125 (18) 1. 2E -2 15 1.2E -2 NO DATA (0) -2.7 - 3.2)E 0 -2.7 - 3.2)E 0 (0/ 18) (0/ 18) 1-131 (18) 1 l.7E -2 15 1. 7E -2 NO DATA (0) -S.9 - 4.8)E -1 -S.9 - 4.8)E -1 (0/ 18) (0/ 18)

Cs-134 (18) lS 2.lE -1 15 2.lE -1 NO DATA (0) -1.8 - 2.2)E 0 -1.8 - 2.2)E 0 (0/ 18) (0/ 18)

Cs-137 (18) 18 7.lE 0 15 7.lE 0 NO DATA (0) 0.0 - 1.4)E 1 0.0 - 1.4)E 1 (14/ 18) (14/ 18)

Ba-140 (18) lS -2.4E -1 15 -2.4E -1 NO DATA (0) -1. 0 - 1.3)E 1 -1. 0 - 1.3)E 1 (0/ 18) (0/ 18)

La-140 (18) lS -1. 9E -1 15 -1. 9E -1 NO DATA (0) -1.S - 1.l)E 0 -1.S - 1.l)E 0 (0/ 18) (0/ 18)

Ce-141 (18) -6.4E -1 15 -6.4E -1 NO DATA (0) -2.9 - 2.S)E 0 -2.9 - 2.S)E 0 (0/ 18) (0/ 18)

Ce-144 (18) -1. SE 0 15 -1. SE 0 NO DATA (0) -9.6 - 4.0)E 0 -9.6 - 4.0)E 0 (0/ 18) (0/ 18)

Pb-212 (18) 1.2E 0 15 l.2E 0 NO DATA (0) -2.S - S.6)E 0 -2.S - S.6)E 0 (0/ 18) (0/ 18)

Pb-214 (18) -l.4E -1 15 -l.4E -1 NO DATA (0) -S.3 - S.3)E 0 -S.3 - S.3)E 0 (0/ 18) (0/ 18)

Bi-214 (18) 4.0E -1 15 4.0E -1 NO DATA (0) -2.9 - 4.0)E 0 -2.9 - 4.0)E 0 (0/ 18) (0/ 18)

Ac-228 (18) -8. 7E -1 15 -8.7E -1 NO DATA (0) -7.2 - 9.3)E 0 -7.2 - 9.3)E 0 (0/ 18) (0/ 18)

Th-228 (18) l.2E 0 15 l.2E 0 NO DATA (0) -2.S - S.6)E 0 -2.S - S.6)E 0 (0/ 18) (0/ 18)

Non-Routine refers to those radionuclides that exceeded the Reporting Levels in ODCM Table A.9.1-3.

- The fraction of detectable measurements (i.e., > MDC with no uncertain identification) is shown in parentheses.

3.4 Surface Water Surface water (seawater - WS) grab samples are required at two locations (control and indicator) monthly. The indicator (WS-01) is over the vicinity of the plant's submerged discharge structure. The control location (WS-

51) is situated in Ipswich Bay, MA, approximately 26.2 km from the plant. A gamma analysis is performed on each sample. A tritium analysis is performed on the quarterly composite of samples from each ODCM required location. Additional samples were collected from the Seabrook Marsh (WS-10) which borders the immediate plant property. The marsh samples are intended to provide indication of any ground water movement across the site area that might carry contamination into the surface waters of the marsh. Each of these samples is analyzed for both gamma emitters and tritium.

For 2020, a total of 26 gamma analyses were performed on surface water samples. The only radionuclides detected were naturally-occurring K-40, which was detected in 25 out of 26 samples, naturally-occurring Pb-212, which was detected in two samples, Bi-214, which was detected in one sample, and Th-228, which was detected in two samples. No plant-related nuclides were detected. The present data for gamma emitters in seawater is consistent with that of the pre-operational program and previous years of operations. Therefore, no increasing or decreasing trends were observed.

Quarterly composites for the required off-shore locations (Stations WS-01 and WS-51) were analyzed for tritium. A total of 8 off-shore samples (composites) were analyzed in 2020. The quarterly composite samples showed no indication of tritium. All samples met the required minimum LLD (3000 pCi/kg) for tritium in seawater. These results are consistent with pre-operational tritium data. The achieved tritium Minimum Detectable Concentration (MDC) for the quarterly off-shore composite samples averaged 424 pCi/kg.

The calculated dose as the result of plant effluents is not evaluated due to the fact that no plant-related radionuclides were or have been detected in the past. Therefore, no increasing or decreasing trends in dose were observed. This sampling program demonstrates that there is no impact to the public or environment, through this pathway from plant operations.

The REMP Summary Table 3.4-1 lists the range of analysis results by radionuclide for Indicator and Control Stations for the sea water environmental media. Attachment 1 to this report lists the individual analysis results for each measurement of sea water under the Sample Type code WS.

Any sample collection and analysis deviations from the ODCM required program or reportable concentrations that may have occurred during the year are described in Section 5.

Table 3.4-1 Radiological Environmental Monitoring Program Summary Seabrook Nuclear Power Station, Seabrook, NH (January - December 2020)

MEDIUM: Sea Water !WS) UNITS: pCi/kg Indicator Stations Station With Highest Mean Control Stations Radionuclides Mean Station Mean Mean (No. Analyses) Required Range Range Range (Non-Routine*) LLD (No. Detected**) (No. Detected**) (No. Detected**)

H-3 (8) 3000 3.3E 1 01 3.3E 1 1.2E 1 (0) -9.1 - 24.5)E 1 -9.1 - 24.5)E 1 -1.8 - 1.4)E 2 (0/ 4) (0/ 4) (0/ 4)

Be-7 (26) 4.0E -1 01 l.lE 0 9.7E -3 (0) -6.5 - 8.4)E 0 -6.5 - 8.4)E 0 -1.2 - 0.6)E 1 (0/ 14) (0/ 12) (0/ 12)

K-40 (26) 30 3.lE 2 01 3.4E 2 3.lE 2 (0) 1.1 - 3.7)E 2 3.1 - 3.7)E 2 2.8 - 3.4)E 2 (14/ 14) (12/ 12) (11/ 12)

Cr-51 (26) -2.6E 0 51 6.8E -1 6.8E -1 (0) -1.5 - 0.9)E 1 -5.7 - 9.9)E 0 -5.7 - 9.9)E 0 (0/ 14) (0/ 12) (0/ 12)

Mn-54 (26) 15 -2.5E -1 01 -1.2E -1 -1. 3E -1 (0) -1.4 - 1.l)E 0 -8.0 - 10.5)E -1 -7.9 - 3.5)E -1 (0/ 14) (0/ 12) (0/ 12)

Co-57 (26) 3.2E -1 01 3.8E -1 -1. 7E -1 (0) -4.7 - 9.7)E -1 -4.7 - 9.7)E -1 -1.7 - 0.3)E 0 (0/ 14) (0/ 12) (0/ 12)

Co-58 (26) 15 5. 5E -2 01 1. 2E -1 -2.4E -1 (0) -1.5 - 1.3)E 0 -1.5 - 1.3)E 0 -6.1 - 3.5)E -1 (0/ 14) (0/ 12) (0/ 12)

Fe-59 (26) 30 1. 3E -1 01 2.6E -1 1. 9E -1 (0) -2.7 - 2.3)E 0 -2.7 - 2.3)E 0 -4.0 - 3.4)E 0 (0/ 14) (0/ 12) (0/ 12)

Co-60 (26) 15 6.7E -1 10 7.9E -1 4.lE -1 (0) -1.4 - 28.8)E -1 4.1 - 11.8)E -1 -1.9 - 1.7)E 0 (0/ 14) (0/ 2) (0/ 12)

Zn-65 (26) 30 l.8E -1 10 8.8E -1 -7.8E -2 (0) -2.4 - 3.0)E 0 3.2 - 172.0)E -2 -2.1 - 1.3)E 0 (0/ 14) (0/ 2) (0/ 12)

Se-75 (26) 7.0E -3 51 2.8E -1 2.8E -1 (0) -1.0 - 1. 6)E 0 -1.5 - l.7)E 0 -1.5 - 1. 7)E 0 (0/ 14) (0/ 12) (0/ 12)

Nb-95 (26) 15 3.0E -1 10 5.0E -1 5.8E -2 (0) -9.4 - 13.5)E -1 -6.3 - 106.0)E -2 -3.5 - 5.3)E -1 (0/ 14) (0/ 2) (0/ 12)

Zr-95 (26) 15 -1. 2E -1 01 -5.lE -2 -2.5E -1 (0) -2.1 - 2.9)E 0 -2.1 - 2.9)E 0 -2.5 - 1.5)E 0 (0/ 14) (0/ 12) (0/ 12)

Ru-103 (26) -4.8E -1 51 -7.0E -2 -7.0E -2 (0) -1.1 - 0.3)E 0 -1.3 - 0.8)E 0 -1.3 - 0.8)E 0 (0/ 14) (0/ 12) (0/ 12)

Ru-106 (26) -4.0E -1 51 l.5E 0 1.5E 0 (0) -1.6 - 0.6)E 1 -7.0 - 9.7)E 0 -7.0 - 9.7)E 0 (0/ 14) (0/ 12) (0/ 12)

Non-Routine refers to those radionuclides that exceeded the Reporting Levels in ODCM Table A.9.1-3.

- The fraction of detectable measurements (i.e., > MDC with no uncertain identification) is shown in parentheses.

Table 3.4-1 (Continued)

Radiological Environmental Monitoring Program Summary Seabrook Nuclear Power Station, Seabrook, NH (January - December 2020)

MEDIUM: Sea Water (WS} UNITS: pCi/kg Indicator Stations Station With Highest Mean Control Stations Radionuclides Mean Station Mean Mean (No. Analyses) Required Range Range Range (Non-Routine*) LLD (No. Detected**) (No. Detected**) (No. Detected**)

Ag-108m (26) -3.9E -2 10 3.9E -2 -1.8E -1 (0) -8.9 - 6.2)E -1 -2.3 - 3.l)E -1 -5.5 - 5.2)E -1 (0/ 14) (0/ 2) (0/ 12)

Ag-110m (26) -2.2E -1 10 -2.0E -1 -3.3E -1 (0) -1.4 - 0.7)E 0 -1.1 - 0.7)E 0 -1.4 - 0.4)E 0 (0/ 14) (0/ 2) (0/ 12)

Sb-124 (26) -2.6E -1 51 3.9E -1 3.9E -1 (0) -2.0 - 3.8)E 0 -1. 7 - 3.2)E 0 -1. 7 - 3.2)E 0 (0/ 14) (0/ 12) (0/ 12)

Sb-125 (26) -2.9E -3 51 2.8E -1 2.8E -1 (0) -1.7 - 3.8)E 0 -2.1 - 2.9)E 0 -2.1 - 2.9)E 0 (0/ 14) (0/ 12) (0/ 12) 1-131 (26) 15 1.9E -1 10 4.7E -1 -2.0E -1 (0) -2.0 - 1.7)E 0 -1.3 - 10.7)E -1 -2.5 - 2.5)E 0 (0/ 14) (0/ 2) (0/ 12)

Cs-134 (26) 15 1. 3E -1 01 2.lE -1 -5.lE -2 (0) -1.8 - 1.2)E 0 -1.8 - 1.2)E 0 -2.9 - 1.3)E 0 (0/ 14) (0/ 12) (0/ 12)

Cs-137 (26) 18 2.0E -1 10 2.7E -1 -2.9E -1 (0) -6.8 - 14.8)E -1 -1.3 - 6.8)E -1 -1.2 - 0.6)E 0 (0/ 14) (0/ 2) (0/ 12)

Ba-140 (26) 15 9.5E -1 01 1.4E 0 5.0E -1 (0) -4.5 - 5.5)E 0 -4.5 - 5.5)E 0 -3.6 - 4.0)E 0 (0/ 14) (0/ 12) (0/ 12)

La-140 (26) 15 -4.5E -1 10 1.lE -1 -9.5E -1 (0) -4.0 - 2.6)E 0 -1.3 - 1.5)E 0 -3.5 - 0.5)E 0 (0/ 14) (0/ 2) (0/ 12)

Ce-141 (26) -1.2E 0 01 -1.lE 0 -1.lE 0 (0) -4.8 - 2.4)E 0 -4.8 - 2.4)E 0 -5 .1 - 1. 6) E 0 (0/ 14) (0/ 12) (0/ 12)

Ce-144 (26) -2.lE -1 51 3.5E -1 3.5E -1 (0) -3.2 - 5.3)E 0 -6.4 - 10.3)E 0 -6.4 - 10.3)E 0 (0/ 14) (0/ 12) (0/ 12)

Pb-212 (26) 9.8E -1 10 1.2E 0 8.4E -2 (0) -5.7 - 8.5)E 0 2.5 - 21.5)E -1 -4.6 - 2.9)E 0 (2/ 14) (0/ 2) (0/ 12)

Pb-214 (26) 6.7E -1 10 1.6E 0 -1.2E 0 (0) -3.7 - 5.9)E 0 1.1 - 31. 4)E -1 -5.8 - 2.8)E 0 (0/ 14) (0/ 2) (0/ 12)

Non-Routine refers to those radionuclides that exceeded the Reporting Levels in ODCM Table A.9.1-3.

- The fraction of detectable measurements (i.e., >MDC with no uncertain identification) is shown in parentheses Table 3.4-1 (Continued)

Radiological Environmental Monitoring Program Summary Seabrook Nuclear Power Station, Seabrook, NH (January - December 2020)

MEDIUM: Sea Water (WS) UNITS: pCi/kg Indicator Stations Station With Highest Mean Control Stations Radionuclides Mean Station Mean Mean (No. Analyses) Required Range Range Range (Non-Routine*) LLD (No. Detected**) (No. Detected**) (No. Detected**)

Bi-214 (26) 2.7E -1 01 6.2E -1 6.lE -1 (0) -2.7 - 3.5)E 0 -2.3 - 3.5)E 0 -2.3 - 10.l)E 0 (0/ 14) (0/ 12) (1/ 12)

Ac-228 (26) l.9E -1 10 l.7E 0 6.7E -1 (0) -1.1 - 0.7)E 1 0.0 - 3.4)E 0 -9.6 - 10.l)E 0 (0/ 14) (0/ 2) (0/ 12)

Th-228 (26) 9.BE -1 10 l.2E 0 8. 4E -2 (0) -5.7 - 8.5)E 0 2.5 - 21. 5) E -1 -4.6 - 2.9)E 0 (2/ 14) (0/ 2) (0/ 12)

Non-Routine refers to those radionuclides that exceeded the Reporting Levels in ODCM Table A.9.1-3.

- The fraction of detectable measurements (i.e., > MDC with no uncertain identification) is shown in parentheses.

3.5 Ground Water There is no requirement in the ODCM to collect ground water (WG) samples. For the year, quarterly ground water samples were collected when available from three locations. These samples were collected from the town water line (WG-01) supplied to the Site (by the Town of Seabrook), from an inactive well (WG-13) located approximately 1 km north of the plant, and from a private well 1.3 km NNW (WG-14). For 2020, a total of 12 samples were collected. All samples were analyzed for gross-beta activity, gamma-emitters and tritium.

Gross beta activity was detected in seven of the twelve samples due to naturally-occurring radium and its daughter products. The gross beta activity is consistent with results from previous years of commercial operations. Figures 3.5 and 3.5.1 indicate the current year (2020) and the long-term measurement history for gross beta in well waters. No tritium or plant-related gamma emitters were detected in any of the ground water samples collected during the year. Table 3.5-1 identifies the results of the search for radionuclides of which only naturally-occurring K-40 was detected in one sample, Pb-212 in one sample, Pb-214 in eight samples, Bi-214 in nine samples, and Th-228 was detected in one of 12 samples.

The dose potential to the public from drinking ground water is not evaluated due to the fact that plant-related radionuclides have not been detected. Therefore, no increasing or decreasing trends were observed. There is no impact to the public, through this pathway, from plant operations.

The REMP Summary Table 3.5-1 lists the range of analysis results by radionuclide for all ground water environmental samples. Attachment 1 to this report lists the individual analysis results for each measurement of ground water under the Sample Type code WG.

Any reportable sample concentrations that may have occurred during the year are described in Section 5.

FIGURE 3.5 GROSS-BETA MEASUREMENTS OF GROUND WATER SEABROOK STATION 20 18 16 14 12 10

~

0..

8 6

4 2

0

-2 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 2020

- O - - IJVG-01 Seabrook Town Wells

- X- 1/VG-1 3 Seabrook Stat ion Well No. 13

- l/VG-14 Brim mer's Lane FIGURE 3.5.1 GROSS-BETA MEASUREMENTS OF GROUND WATER SEMI-ANNUAL AVERAGES SEABROOK STATION 18 13 Cl x x

~

G

a. 8 x

01\J<x x

3

-2 +--.--~~~~~~~~~~~~~~~-.-~~~~~~~~~~~~~~-.--~

1990 1992 1994 1996 1998 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020

-x-WG-01 Seabrook Town Wells

- - wG-14Brimmer's Lane

--o-- WG-13 Seabrook Station W911 No. 13 Table 3.5-1 Radiological Environmental Monitoring Program Summary Seabrook Nuclear Power Station, Seabrook, NH (January - December 2020)

MEDIUM: Ground Water (WGI UNITS: pCi/kg Indicator Stations Station With Highest Mean Control Stations Radionuclides Mean Station Mean Mean (No. Analyses) Required Range Range Range (Non-Routine*) LLD (No. Detected**) (No. Detected**) (No. Detected**)

BETA (12) 4 3.7E 0 01 4.5E 0 NO DATA (0) 1.3 - 751.0)E -2 1.3 - 751.0)E -2 (7 I 12> (3/ 4)

H-3 (12) 3000 6.4E 1 14 1.lE 2 NO DATA (0) -1.3 - 2.5)E 2 -2.5 - 24.6)E 1 (0/ 12) (0/ 4)

Be-7 (12) -2.5E 0 13 -1. 6E 0 NO DATA (0) -9.5 - 1.8)E 0 -3.3 - O.O)E 0 (0/ 12) (0/ 4)

K-40 (12) 30 -2.lE 0 13 l.2E 0 NO DATA (0) -2.1 - 2.6)E 1 -2.1 - 2.6)E 1 (1/ 12) (1/ 4)

Cr-51 (12) -1. 6E 0 01 -6.8E -1 NO DATA (0) -1.1 - 0.6)E 1 -6.6 - 6.4)E 0 (0/ 12) (0/ 4)

Mn-54 (12) 15 -1.8E -1 01 6.5E -3 NO DATA (0) -8.7 - 9.4)E -1 -5.4 - 9.4)E -1 (0/ 12) (0/ 4)

Co-57 (12) l.2E -1 13 1.8E -1 NO DATA (0) -4.7 - 8.8)E -1 -3.2 - 8.3)E -1 (0/ 12) (0/ 4)

Co-58 (12) 15 1. 4E -1 14 8.4E -1 NO DATA (0) -2.1 - 1.8)E 0 2.9 - 18.l)E -1 (0/ 12) (0/ 4)

Fe-59 (12) 30 -2.0E -1 01 5.4E -1 NO DATA (0) -3.1 - 3.6)E 0 -3.0 - 3.6)E 0 (0/ 12) (0/ 4)

Co-60 (12) 15 4.4E -2 01 2. 9E -1 NO DATA (0) -6.0 - 12.6)E -1 -6.0 - 12.6)E -1 (0/ 12) (0/ 4)

Zn-65 (12) 30 4.0E -1 01 1. 6E 0 NO DATA (0) -2.5 - 3.6)E 0 -1.0 - 3.6)E 0 (0/ 12) (0/ 4)

Se-75 (12) -1.3E -1 13 3.4E -1 NO DATA (0) -1.4 - 1.3)E 0 -3.1 - 130.0)E -2 (0/ 12) (0/ 4)

Nb-95 (12) 15 5.3E -1 14 9.8E -1 NO DATA (0) -7.9 - 15.8)E -1 4.7 - 14.5)E -1 (0/ 12) (0/ 4)

Non-Routine refers to those radionuclides that exceeded the Reporting Levels in ODCM Table A.9.1-3.

- The fraction of detectable measurements (i.e., > MDC with no uncertain identification) is shown in parentheses.

Table 3.5-1 (Continued)

Radiological Environmental Monitoring Program Summary Seabrook Nuclear Power Station, Seabrook, NH (January - December 2020)

MEDIUM: Ground Water (WG} UNITS: ~Ci/kg Indicator Stations Station With Highest Mean Control Stations Radionuclides Mean Station Mean Mean (No. Analyses) Required Range Range Range (Non-Routine*) LLD (No. Detected**) (No. Detected**) (No. Detected**)

Zr-95 (12) 15 2.5E -1 14 5.2E -1 NO DATA (0) -2.2 - 2.4)E 0 -1.6 - 2.4)E 0 (0/ 12) (0/ 4)

Ru-103 (12) -2.lE -1 01 2.4E -1 NO DATA (0) -1.5 - 1. 7)E 0 -9.9 - 16.9)E -1 (0/ 12) (0/ 4)

Ru-106 (12) 3.2E -1 13 2.4E 0 NO DATA (0) -6.7 - 9.7)E 0 -4.1 - 6.8)E 0 (0/ 12) (0/ 4)

Ag-108m (12) -6.6E -2 13 4.lE -1 NO DATA (0) -7.7 - 12.0)E -1 -3.3 - 12.0)E -1 (0/ 12) (0/ 4)

Ag-110m (12) -1.lE -1 14 4.4E -1 NO DATA (0) -2.3 - 1.4)E 0 -3.4 - 13.5)E -1 (0/ 12) (0/ 4)

Sb-124 (12) 1.4E -1 01 6.5E -1 NO DATA (0) -1.7 - 2.7)E 0 -1.1 - 2.l)E 0 (0/ 12) (0/ 4)

Sb-125 (12) -1.8E -1 13 6.2E -1 NO DATA (0) -2.8 - 3.6)E 0 -9.2 - 14.8)E -1 (0/ 12) (0/ 4) 1-131 (12) 15 8.7E -3 13 7.3E -1 NO DATA (0) -2.7 - 2.9)E 0 -4.2 - 29.4)E -1 (0/ 12) (0/ 4)

Cs-134 (12) 15 1.9E -1 14 6.lE -1 NO DATA (0) -8.4 - 15.l)E -1 -6.3 - 151.0)E -2 (0/ 12) (0/ 4)

Cs-137 (12) 18 3.2E -1 01 6.9E -1 NO DATA (0) -7.3 - 17.5)E -1 1.6 - 11.4)E -1 (0/ 12) (0/ 4)

Ba-140 (12) 15 3.3E -1 14 8.0E -1 NO DATA (0) -4.3 - 7.3)E 0 -2.3 - 7.3)E 0 (0/ 12) (0/ 4)

La-140 (12) 15 -2.lE -1 01 -1.4E -3 NO DATA (0) -1.5 - 1.l)E 0 -1.5 - 1.l)E 0 (0/ 12) (0/ 4)

Ce-141 (12) -4.lE -1 01 9.4E -1 NO DATA (0) -4.5 - 2.6)E 0 -4.7 - 26.4)E -1 (0/ 12) (0/ 4)

Non-Routine refers to those radionuclides that exceeded the Reporting Levels in ODCM Table A.9.1-3.

- The fraction of detectable measurements (i.e., >3 standard deviations with no uncertain identification) is shown in parentheses.

Table 3.5-1 (Continued)

Radiological Environmental Monitoring Program Summary Seabrook Nuclear Power Station, Seabrook, NH (January - December 2020)

MEDIUM: Ground Water (WG} UNITS: pCi/kg Indicator Stations Station With Highest Mean Control Stations Radionuclides Mean Station Mean Mean (No. Analyses) Required Range Range Range (Non-Routine*) LLD (No. Detected**) (No. Detected**) (No. Detected**)

Ce-144 (12) 3.8E -1 13 1.4E 0 NO DATA (0) -4.7 - 5.6)E 0 -2.4 - 3.2)E 0 (0/ 12) (0/ 4)

Pb-212 (12) l.2E 0 13 2.2E 0 NO DATA (0) -1.8 - 6.0)E 0 -9.6 - 59.8)E -1 (1/ 12) (1/ 4)

Pb-214 (12) 8.lE 1 14 2.0E 2 NO DATA (0) -2.4 - 274.0)E 0 7.3 - 27.4)E 1 (8/ 12) (4/ 4)

Bi-214 (12) 7.6E 1 14 1.9E 2 NO DATA (0) -9.0 - 2580.0)E -1 6.6 - 25.8)E 1 (9/ 12) (4/ 4)

Ac-228 (12) -9.9E -1 14 7.3E -1 NO DATA (0) -1.0 - 0.7)E 1 -2.7 - 5.8)E 0 (0/ 12) (0/ 4)

Th-228 (12) l.2E 0 13 2.2E 0 NO DATA (0) -1.8 - 6.0)E 0 -9.6 - 59.8)E -1 (1/ 12) (1/ 4)

Non-Routine refers to those radionuclides that exceeded the Reporting Levels in ODCM Table A.9.1-3.

- The fraction of detectable measurements (i.e., > MDC with no uncertain identification) is shown in parentheses.

3.6 Sediment Semiannual sediment sampling is required at one indicator location, although a total of five locations, three indicators and two controls, are collected. The indicator stations are comprised of two sets of beach sediment cores from Hampton Beach (SE-07) and Seabrook Beach (SE-08), plus two sub-tidal sediment cores taken from near the discharge structure (SE-02). The control locations, Plum Island Beach (SE-57) and sub-tidal Ipswich Bay (SE-52), are both located within Ipswich Bay. A total of 10 samples were collected for the year from all locations. All cores were analyzed as single or whole samples without segmenting. A gamma analysis was performed on each core.

Table 3.6-1 identifies the results of the search for radionuclides of which several naturally-occurring were detected. The naturally-occurring radionuclides include Be-7, K-40 and nuclides of the Uranium-238 decay chain (Th-230, Ra-226, Pb-214 and Bi-214) and the Thorium-232 decay chain (Ac-228, Th-228, Pb-212, and Tl-208). No plant-related radionuclides were detected in any core. No increasing or decreasing trends were observed. This is consistent with the pre-operational program and with previous years of plant operations. There is no plant related dose to the public or impact to the environment from any pathways associated with this media.

The REMP Summary Table 3.6-1 lists the range of analysis results by radionuclide for Indicator and Control Stations for the sediment environmental media. Attachment 1 to this report fists the individual analysis results for each measurement of sediment under the Sample Type code SE.

Any sample collection and analysis deviations from the ODCM required program, or reportable concentrations that may have occurred during the year are described in Section 5.

Table 3.6-1 Radiological Environmental Monitoring Program Summary Seabrook Nuclear Power Station, Seabrook, NH (January - December 2020)

MEDIUM: Sediment (SE} UNITS: i;iCi/kg Indicator Stations Station With Highest Mean Control Stations Radionuclides Mean Station Mean Mean (No. Analyses) Required Range Range Range (Non-Routine*) LLD (No. Detected**) (No. Detected**) (No. Detected**)

Be-7 (10) -9.lE 0 57 2.9E 2 2.4E 2 (0) -1.4 - l.3)E 2 2.2 - 3.6)E 2 -2.6 - 390.0)E 0 (0/ 6) (1/ 2) (1/ 4)

K-40 (10) l.BE 4 08 2.lE 4 l.7E 4 (0) 1.4 - 2.4)E 4 1.9 - 2.4)E 4 1.3 - 2.2)E 4 (6/ 6) (2/ 2) (4/ 4)

Cr-51 (10) 2.9E 0 52 l.9E 2 l.6E 2 (0) -7.5 - 6.6)E 1 -4.7 - 43.l)E 1 -4.7 - 43.l)E 1 (0/ 6) (0/ 2) (0/ 4)

Mn-54 (10) 5.9E 0 52 l.7E 1 8.BE 0 (0) -1.3 - 2.6)E 1 6.6 - 28.l)E 0 -6.7 - 28.l)E 0 (0/ 6) (0/ 2) (0/ 4)

Co-57 (10) -1. 6E -1 08 5.9E 0 1. 6E -1 (0) -1.l - 0.7)E 1 5.1 - 6.7)E 0 -1. 7 - l.l)E 1 (0/ 6) (0/ 2) (0/ 4)

Co-58 (10) -8.4E 0 52 8.4E 0 3.9E 0 (0) -4.2 - O.B)E 1 -3.6 - 20.4)E 0 -5.8 - 20.4)E 0 (0/ 6) (0/ 2) (0/ 4)

Fe-59 (10) -4.BE 0 07 2.5E 1 -1. lE 1 (0) -5.6 - 3.B)E 1 1.3 - 3.8)E 1 -3.3 - 0.6)E 1 (0/ 6) (0/ 2) (0/ 4)

Co-60 (10) l.7E 0 02 l.9E 1 -5. lE 0 (0) -1.9 - 4.0)E 1 -1.6 - 39.6)E 0 -1.5 - 0.5)E 1 (0/ 6) (0/ 2) (0/ 4)

Zn-65 (10) -1. lE 1 08 2.6E 1 -3.6E 1 (0) -9.1 - 4.2)E 1 1.1 - 4.2)E 1 -7.4 - -l.5)E 1 (0/ 6) (0/ 2) (0/ 4)

Se-75 (10) 4.7E 0 07 l.5E 1 -2.4E -1 (0) -1.2 - 2.2)E 1 7.7 - 22.3)E 0 -1.1 - 0.9)E 1 (0/ 6) (0/ 2) (0/ 4)

Nb-95 (10) 7.2E 0 02 3.3E 1 5.5E 0 (0) -1.4 - 3.B)E 1 2.9 - 3.8)E 1 -8.9 - 20.4)E 0 (0/ 6) (0/ 2) (0/ 4)

Zr-95 (10) 3.lE 1 02 5.9E 1 l.7E 1 (0) -1.0 - 8.6)E 1 3.1 - 8.6)E 1 -2.3 - 5.7)E 1 (0/ 6) (0/ 2) (0/ 4)

Ru-103 (10) -6.9E 0 57 3.6E 0 2.lE 0 (0) -3.4 - 1. 5) E 1 -8.9 - 80.3)E -1 -4.9 - 8.0)E 0 (0/ 6) (0/ 2) (0/ 4)

Non-Routine refers to those radionuclides that exceeded the Reporting Levels in ODCM Table A.9.1-3.

- The fraction of detectable measurements (i.e., >MDC with no uncertain identification) is shown in parentheses.

Table 3.6-1 (Continued)

Radiological Environmental Monitoring Program Summary Seabrook Nuclear Power Station, Seabrook, NH (January - December 2020)

MEDIUM: Sediment {SE} UNITS: 12Ci/kg Indicator Stations Station With Highest Mean Control Stations Radionuclides Mean Station Mean Mean (No. Analyses) Required Range Range Range (Non-Routine*) LLD (No. Detected**) (No. Detected**) (No. Detected**)

Ru-106 (10) -9.9E 0 57 1.lE 2 1.lE 2 (0) -5.7 - 7.6)E 1 6.0 - 16.4)E 1 5.9 - 16.4)E 1 (0/ 6) (0/ 2) (0/ 4)

Ag-108m (10) 5.2E 0 07 8.0E 0 -2.lE 0 (0) -3.5 - 19.5)E 0 -3.5 - 19.5)E 0 -3.7 - 1.4)E 0 (0/ 6) (0/ 2) (0/ 4)

Ag-110m (10) 1.2E 0 08 1.5E 1 -2.0E 0 (0) -2.0 - 3.5)E 1 -4.8 - 35.l)E 0 -6.1 - 0.6)E 0 (0/ 6) (0/ 2) (0/ 4)

Sb-124 (10) -1. 7E 1 57 9.2E 0 5.4E 0 (0) -5.7 - O.B)E 1 5.5 - 12.9)E 0 -2.7 - 3.0)E 1 (0/ 6) (0/ 2) (0/ 4)

Sb-125 (10) 7.4E 0 08 2.0E 1 -2.3E 1 (0) -3.1 - 2.3)E 1 1.7 - 2.3)E 1 -3.8 - O.l)E 1 (0/ 6) (0/ 2) (0/ 4) 1-131 (10) -1.5E 1 57 8.lE 1 7.7E 1 (0) -1. 7 - 1. 9) E 2 9.6 - 152.0)E 0 -9.0 - 155.0)E 0 (0/ 6) (0/ 2) (0/ 4)

Cs-134 (10) 150 1.5E 1 02 2.5E 1 9.2E 0 (0) 0.0 - 4.9)E 1 0.0 - 4.9)E 1 0.0 - 3.7)E 1 (0/ 6) (0/ 2) (0/ 4)

Cs-137 (10) 180 -4.6E -1 02 7.lE 0 -7.3E -2 (0) -5.6 - 8.6)E 0 5.6 - 8.6)E 0 -1.9 - 1.0)E 1 (0/ 6) (0/ 2) (0/ 4)

Ba-140 (10) 5.7E 1 07 1.BE 2 1.2E 2 (0) -1.6 - 3.9)E 2 -2.6 - 39.4)E 1 1.0 - 28.6)E 1 (0/ 6) (0/ 2) (0/ 4)

La-140 (10) -3.7E 1 57 9.3E 1 5.lE 1 (0) -1.4 - O.O)E 2 -8.1 - 194.0)E 0 -8.1 - 194.0)E 0 (0/ 6) (0/ 2) (0/ 4)

Ce-141 (10) -1. 9E 1 07 2.lE 1 -1. BE 1 (0) -7.5 - 5.0)E 1 -8.9 - 50.4)E 0 -5.7 - 0.9)E 1 (0/ 6) (0/ 2) (0/ 4)

Ce-144 (10) -8.6E 0 07 6.2E 1 1.4E 1 (0) -1.1 - 1.2)E 2 3.8 - 120.0)E 0 -4.7 - 6.7)E 1 (0/ 6) (0/ 2) (0/ 4)

Tl-208 (10) 2.4E 2 52 8.4E 2 4.9E 2 (0) 8.1 - 52.4)E 1 3.7 - 13.l)E 2 1.1 - 13.l)E 2 (6/ 6) (2/ 2) (4/ 4)

Non-Routine refers to those radionuclides that exceeded the Reporting Levels in ODCM Table A.9.1-3.

- The fraction of detectable measurements (i.e., > MDC with no uncertain identification) is shown in parentheses.

Table 3.6-1 (Continued)

Radiological Environmental Monitoring Program Summary Seabrook Nuclear Power Station, Seabrook, NH (January - December 2020)

MEDIUM: Sediment (SE} UNITS: pCi/kg Indicator Stations Station With Highest Mean Control Stations Radionuclides Mean Station Mean Mean (No. Analyses) Required Range Range Range (Non-Routine*) LLD (No. Detected**) (No. Detected**) (No. Detected**)

Pb-212 (10) 8.lE 2 52 2.9E 3 1.7E 3 (0) 3.6 - 18.6)E 2 1.2 - 4.5)E 3 4.5 - 45.4)E 2 (6/ 6) (2/ 2) (4/ 4)

Pb-214 (10) 6.0E 2 52 2.0E 3 l.2E 3 (0) 1. 8 - 13. 7) E 2 9.0 - 31.7)E 2 3.7 - 31.7)E 2 (6/ 6) (2/ 2) (4/ 4)

Bi-214 (10) 5.3E 2 52 1.6E 3 9.2E 2 (0) 2.5 - 10.9)E 2 7.7 - 23.9)E 2 2.6 - 23.9)E 2 (6/ 6) (2/ 2) (4/ 4)

Ra-226 (10) 5.3E 2 52 1.6E 3 9.2E 2 (0) 2.5 - 10.9)E 2 7.7 - 23.9)E 2 2.6 - 23.9)E 2 (6/ 6) (2/ 2) (4/ 4)

Ac-228 (10) 7.lE 2 52 2.8E 3 1.6E 3 (0) 0.0 - 1.7)E 3 1.2 - 4.3)E 3 2.9 - 43.2)E 2 (5/ 6) (2/ 2) (4/ 4)

Th-228 (10) 8.lE 2 52 2.9E 3 1.7E 3 (0) 3.6 - 18.6)E 2 1.2 - 4.5)E 3 4.5 - 45.4)E 2 (6/ 6) (2/ 2) (4/ 4)

Th-230 (10) 5.3E 2 52 1.6E 3 9.2E 2 (0) 2.5 - 10.9)E 2 7.7 - 23.9)E 2 2.6 - 23.9)E 2 (6/ 6) (2/ 2) (4/ 4)

Non-Routine refers to those radionuclides that exceeded the Reporting Levels in ODCM Table A.9.1-3.

- The fraction of detectable measurements (i.e., > MDC with no uncertain identification) is shown in parentheses.

3.7 Fish Semiannual fish (FH) and invertebrate samples are required by the ODCM REMP from two locations.

Quarterly collections are attempted to ensure the sampling requirements are met. This section presents the results for fish sampling only. Invertebrate results may be found in Sections 3.8 and 3.9, entitled Lobsters and Shellfish, respectively.

During the year, a total of 10 fish samples were collected. The fish species available from Station FH-03 (indicator station) and Station FH-53 (control station) were dominated by Winter Flounder which are bottom dwelling species. One sample of Gunner fish was also collected from sample location FH-06 (Hampton Bay in the area of the plant's discharge).

A gamma analysis was performed on the edible portion of each sample collected. In 2020, the only radionuclides detected were naturally-occurring K-40 (all samples). Table 3.7-1 summarizes the results for radionuclides in fish. Similar to past years, no plant-related radionuclides were detected in any samples. As a result, no increasing or decreasing trends were observed. Subsequently, there is no dose to the public or impact to the environment through this pathway due to plant operations. This is consistent with previous years of plant operations, as well as the pre-operational program.

In addition to the required program for fish as defined in the ODCM, sampling was attempted to collect a local fish species (cunner fish) that resides in the upper regions of the water column using an alternate collection method from that used for the more prevalent bottom species (flounder). For 2020, one Gunner sample was collected from Hampton Bay. The results are listed in Attachment 1 as laboratory number 513410003 (05/27/2020). No plant radionuclides were detected in the Gunner fish samples, with only naturally-occurring K-40 being found.

The REMP Summary Table 3.7-1 also lists the range of analysis results by radionuclide for Indicator and Control Stations for all fish environmental media. Attachment 1 to this report lists the individual analysis results for each measurement of fish under the Sample Type code FH.

Any sample collection and analysis deviations from the ODCM required program, or reportable concentrations that may have occurred during the year are described in Section 5.

Table 3.7-1 Radiological Environmental Monitoring Program Summary Seabrook Nuclear Power Station, Seabrook, NH (January - December 2020)

MEDIUM: Fish {FH} UNITS: i;iCi/kg Indicator Stations Station With Highest Mean Control Stations Radionuclides Mean Station Mean Mean (No. Analyses) Required Range Range Range (Non-Routine*) LLD (No. Detected**) (No. Detected**) (No. Detected**)

Be-7 (10) 7.8E 0 03 8.5E 0 -1. lE 1 (0) -9.9 - 32.l)E 0 -9.9 - 32.l)E 0 -2.6 - 0.7)E 1 (0/ 6) (0/ 5) (0/ 4)

K-40 (10) 3.2E 3 06 3.3E 3 3.2E 3 (0) 2.7 - 3.5)E 3 2.6 - 3.5)E 3 (6/ 6) (1/ 1) (4/ 4)

Cr-51 (10) -1. lE 0 53 l.lE 1 l.lE 1 (0) -3.7 - 4. 6)E 1 -2.5 - 3.4)E 1 -2.5 - 3.4)E 1 (0/ 6) (0/ 4) (0/ 4)

Mn-54 (10) 130 1.9E 0 06 2.lE 0 1. 7E -1 (0) -2.0 - 53.6)E -1 -3.2 - 5.3)E 0 (0/ 6) (0/ 1) (0/ 4)

Co-57 (10) -3.6E -1 53 l.8E -1 l.8E -1 (0) -2.2 - 2.8)E 0 -1. 2 - l.2)E 0 -1.2 - l.2)E 0 (0/ 6) (0/ 4) (0/ 4)

Co-58 (10) 130 -3.2E -1 53 9.7E -1 9.7E -1 (0) -3.4 - 4.2)E 0 -2.4 - 7.2)E 0 -2.4 - 7.2)E 0 (0/ 6) (0/ 4) (0/ 4)

Fe-59 (10) 260 9.2E -1 06 8.2E 0 2.2E 0 (0) -7.3 - 8.2)E 0 -1.3 - 6.5)E 0 (0/ 6) (0/ 1) (0/ 4)

Co-60 (10) 130 2.2E 0 06 2.4E 0 7.4E -1 (0) -4.9 - 63.S)E -1 -3.0 - 4.5)E 0 (0/ 6) (0/ 1) (0/ 4)

Zn-65 (10) 260 1.7E 0 06 4.3E 0 3.3E 0 (0) -6.6 - 4.3)E 0 1.3 - 6.l)E 0 (0/ 6) (0/ 1) (0/ 4)

Se-75 (10) -9.4E -1 06 3.9E 0 -1. SE -2 (0) -4.9 - 3.9)E 0 -2.0 - l.3)E 0 (0/ 6) (0/ 1) (0/ 4)

Nb-95 (10) -1. 6E 0 53 2.lE 0 2.lE 0 (0) -4.5 - 0.5)E 0 9.1 - 49.6)E -1 9.1 - 49.6)E -1 (0/ 6) (0/ 4) (0/ 4)

Zr-95 (10) -4.0E 0 53 2.0E 0 2.0E 0 (0) -8.5 - 3.0)E 0 -4.4 - 5.7)E 0 -4.4 - 5.7)E 0 (0/ 6) (0/ 4) (0/ 4)

Ru-103 (10) -6.4E -1 06 l.2E 0 3.7E -1 (0) -2.6 - 1. 8) E 0 -8.9 - 12.l)E -1 (0/ 6) (0/ 1) (0/ 4)

Non-Routine refers to those radionuclides that exceeded the Reporting Levels in ODCM Table A.9.1-3.

- The fraction of detectable measurements (i.e., >MDC with no uncertain identification) is shown in parentheses.

Table 3.7-1 (Continued)

Radiological Environmental Monitoring Program Summary Seabrook Nuclear Power Station, Seabrook, NH (January - December 2020)

MEDIUM: Fish (FHl UNITS: pCi/kg Indicator Stations Station With Highest Mean Control Stations Radionuclides Mean Station Mean Mean (No. Analyses) Required Range Range Range (Non-Routine*) LLD (No. Detected**) (No. Detected**) (No. Detected**)

Ru-106 (10) -5.9E -1 06 4.0E 1 -4.2E 0 (0) -4.1 - 4.0)E 1 -1. 4 - 1.l)E 1 (0/ 6) (0/ 1) (0/ 4)

Ag-108m (10) 2.5E 0 03 2.5E 0 2.0E -1 (0) -7.7 - 7990.0)E -3 -7.7 - 7990.0)E -3 -2.9 - 3.l)E 0 (0/ 6) (0/ 5) (0/ 4)

Ag-110m (10) -l.5E 0 53 -4.9E -1 -4.9E -1 (0) -5.6 - 2.3)E 0 -2.0 - 2.5)E 0 -2.0 - 2.5)E 0 (0/ 6) (0/ 4) (0/ 4)

Sb-124 (10) 1. 5E -1 06 3.6E 0 -3.8E 0 (0) -5.2 - 5.0)E 0 -2.2 - 0.4)E 1 (0/ 6) (0/ 1) (0/ 4)

Sb-125 (10) 2.5E 0 03 3.lE 0 l.9E 0 (0) -2.6 - 9.9)E 0 -2.6 - 9.9)E 0 -1.1 - 10.0)E 0 (0/ 6) (0/ 5) (0/ 4) 1-131 (10) -2.3E 0 53 3.4E 0 3.4E 0 (0) -1.9 - l.6)E 1 4.4 - 53.8)E -1 4.4 - 53.8)E -1 (0/ 6) (0/ 4) (0/ 4)

Cs-134 (10) 130 3.8E -1 06 5.9E 0 -4.lE -1 (0) -2.9 - 5.9)E 0 -4.8 - 2.l)E 0 (0/ 6) (0/ 1) (0/ 4)

Cs-137 (10) 150 l.3E 0 06 2.2E 0 7.9E -1 (0) -2.3 - 5.l)E 0 -3.6 - 6.7)E 0 (0/ 6) (0/ 1) (0/ 4)

Ba-140 (10) 1.lE 0 06 l.7E 1 6.5E 0 (0) -1.9 - 1.8)E 1 -3.6 - 24.2)E 0 (0/ 6) (0/ 1) (0/ 4)

La-140 (10) 4.5E -2 03 9.6E -1 -3.5E -1 (0) -5.5 - 10.2)E 0 -5.5 - 10.2)E 0 -3.6 - l.4)E 0 (0/ 6) (0/ 5) (0/ 4)

Ce-141 (10) -1. lE 0 06 6.9E -1 3.2E -1 (0) -3.0 - 0.8)E 0 -2.8 - 2.7)E 0 (0/ 6) (0/ 1) (0/ 4)

Ce-144 (10) -1. 6E 0 53 6.0E 0 6.0E 0 (0) -2.4 - 0.9)E 1 2.9 - 9. 6)E 0 2.9 - 9.6)E 0 (0/ 6) (0/ 4) (0/ 4)

Tl-208 (10) l.7E -1 03 4.7E -1 -1. 7E 0 (0) -2.8 - 1. 9) E 0 -2.8 - 1. 9)E 0 -6.6 - 4.2)E 0 (0/ 6) (0/ 5) (0/ 4)

Non-Routine refers to those radionuclides that exceeded the Reporting Levels in ODCM Table A.9.1-3.

- The fraction of detectable measurements (i.e., > MDC with no uncertain identification) is shown in parentheses.

Table 3.7-1 (Continued)

Radiological Environmental Monitoring Program Summary Seabrook Nuclear Power Station, Seabrook, NH (January - December 2020)

MEDIUM: Fish IFH) UNITS: pCi/kg Indicator Stations Station With Highest Mean Control Stations Radionuclides Mean Station Mean Mean (No. Analyses) Required Range Range Range (Non-Routine*) LLD (No. Detected**) (No. Detected**) (No. Detected**)

Pb-212 (10) l.7E 0 03 2.2E 0 -2.6E 0 (0) -3.5 - 10.4)E 0 -3.5 - 10.4)E 0 -1. 8 - 1. 0) E 1 (0/ 6) (0/ 5) (0/ 4)

Pb-214 (10) -3.?E -2 06 4.7E 0 3. 6E 0 (0) -1.1 - 1.l)E 1 -4.2 - 83.?)E -1 (0/ 6) (0/ 1) (0/ 4)

Bi-214 (10) 1. 6E 0 53 6.0E 0 6.0E 0 (0) -6.6 - 5.B)E 0 -2.5 - 29.3)E 0 -2.5 - 29.3)E 0 (0/ 6) (0/ 4) (0/ 4)

Ra-226 (10) 1.6E 0 53 6.0E 0 6.0E 0 (0) -6.6 - 5.B)E 0 -2.5 - 29.3)E 0 -2.5 - 29.3)E 0 (0/ 6) (0/ 4) (0/ 4)

Ac-228 (10) -4.BE 0 06 9.5E 0 -1. BE 0 (0) -1.2 - 0.9)E 1 -2.0 - 1.B)E 1 (0/ 6) (0/ 1) (0/ 4)

Th-228 (10) l.7E 0 03 2.2E 0 -2.6E 0 (0) -3.5 - 10.4)E 0 -3.5 - 10.4)E 0 -1.8 - 1.0)E 1 (0/ 6) (0/ 5) (0/ 4)

Th-230 (10) 1.6E 0 53 6.0E 0 6.0E 0 (0) -6.6 - 5.B)E 0 -2.5 - 29.3)E 0 -2.5 - 29.3)E 0 (0/ 6) (0/ 4) (0/ 4)

Non-Routine refers to those radionuclides that exceeded the Reporting Levels in ODCM Table A.9.1-3.

- The fraction of detectable measurements (i.e., > MDC with no uncertain identification) is shown in parentheses.

3.8 Lobsters Semiannual fish and invertebrate samples were required from two locations. This section provides the results for one type of invertebrate - Homarus americanus (American lobsters) which is an important commercial food species from local waters. Lobsters (HA) were collected from an indicator location near the discharge (HA-04) and from a control location (HA-54) within Ipswich Bay. A total of four samples were collected for the year.

Fish and shellfish results may be found in Sections 3.7 and 3.9, respectively.

A gamma analysis was performed on each sample. The only radionuclides detected in lobster samples in 2020 were naturally-occurring K-40 (all samples) and Ac-228 (one sample). Similar to past years, no plant-related radionuclides were detected in any sample. Therefore, no increasing or decreasing trends were observed. Consequently, there is no dose to the public or impact to the environment from this pathway due to plant operations. This is consistent with previous years as well as the pre-operational program.

The REMP Summary Table 3.8-1 also lists the range of analysis results by radionuclide for Indicator and Control Stations for all lobster samples. Attachment 1 to this report lists the individual analysis results for each measurement of lobsters under the Sample Type code HA.

Any sample collection and analysis deviations from the ODCM required program, or reportable concentrations that may have occurred during the year are described in Section 5.

Table 3.8-1 Radiological Environmental Monitoring Program Summary Seabrook Nuclear Power Station, Seabrook, NH (January - December 2020)

MEDIUM: American Lobster (HA) UNITS: pCi/kg Indicator Stations Station With Highest Mean Control Stations Radionuclides Mean Station Mean Mean (No. Analyses) Required Range Range Range (Non-Routine*) LLD (No. Detected**) (No. Detected**) (No. Detected**)

Be-7 (4) -2.lE 1 54 2.9E 1 2.9E 1 (0) -4.2 - O.O)E 1 2.1 - 3.7)E 1 2.1 - 3.7)E 1 (0/ 2) (0/ 2) (0/ 2)

K-40 (4) 2.lE 3 54 2.2E 3 2.2E 3 (0) 2.0 - 2.3)E 3 1.9 - 2.6)E 3 1. 9 - 2.6)E 3 (2/ 2) (2/ 2) (2/ 2)

Cr-51 (4) -5.8E 0 54 6.5E -1 6.5E -1 (0) -1.5 - 0.4)E 1 -1.2 - l.3)E 1 -1.2 - 1.3)E 1 (0/ 2) (0/ 2) (0/ 2)

Mn-54 (4) 130 -1. 4E -1 54 3.2E 0 3.2E 0 (0) -3.7 - 0.8)E -1 7.5 - 55.7)E -1 7.5 - 55.7)E -1 (0/ 2) (0/ 2) (0/ 2)

Co-57 (4) 1.lE 0 04 1.lE 0 -6.6E -1 (0) 1.0 - l.2)E 0 1.0 - 1.2)E 0 -1. 0 - -0.3)E 0 (0/ 2) (0/ 2) (0/ 2)

Co-58 (4) 130 2.6E 0 04 2.6E 0 l.4E 0 (0) 9.4 - 42.7)E -1 9.4 - 42.7)E -1 -3.0 - 5.8)E 0 (0/ 2) (0/ 2) (0/ 2)

Fe-59 (4) 260 -4.9E 0 04 -4.9E 0 -5.2E 0 (0) -1.0 - O.l)E 1 -1. 0 - O.l)E 1 -9.9 - -0.4)E 0 (0/ 2) (0/ 2) (0/ 2)

Co-60 (4) 130 1.0E 0 04 l.OE 0 -1.6E 0 (0) -3.8 - 24.l)E -1 -3.8 - 24.l)E -1 -2.6 - -0.7)E 0 (0/ 2) (0/ 2) (0/ 2)

Zn-65 (4) 260 3.8E 0 04 3.8E 0 -3.8E 0 (0) 1. 0 - 6.6)E 0 1. 0 - 6.6)E 0 -5.9 - -1.7)E 0 (0/ 2) (0/ 2) (0/ 2)

Se-75 (4) -1. 5E 0 54 -5.7E -1 -5.7E -1 (0) -2.2 - -0.8)E 0 -7.7 - -3.7)E -1 -7.7 - -3.7)E -1 (0/ 2) (0/ 2) (0/ 2)

Nb-95 (4) 5.0E -4 04 5.0E -4 -7.5E -1 (0) -3.2 - 3.2)E -1 -3.2 - 3.2)E -1 -6.4 - 4.9)E 0 (0/ 2) (0/ 2) (0/ 2)

Zr-95 (4) 4.lE 0 04 4.lE 0 -5.lE 0 (0) 1.2 - 7.l)E 0 1.2 - 7.l)E 0 -8.7 - -1. 6)E 0 (0/ 2) (0/ 2) (0/ 2)

Ru-103 (4) 2.6E 0 54 2.8E 0 2.8E 0 (0) 2.0 - 49.0)E -1 2.7 - 2.8)E 0 2.7 - 2.8)E 0 (0/ 2) (0/ 2) (0/ 2)

Non-Routine refers to those radionuclides that exceeded the Reporting Levels in ODCM Table A.9.1-3.

- The fraction of detectable measurements (i.e., >MDC with no uncertain identification) is shown in parentheses.

Table 3.8-1 (Continued)

Radiological Environmental Monitoring Program Summary Seabrook Nuclear Power Station, Seabrook, NH (January - December 2020)

MEDIUM: American Lobster (HA! UNITS: pCi/kg Indicator Stations Station With Highest Mean Control Stations Radionuclides Mean Station Mean Mean (No. Analyses) Required Range Range Range (Non-Routine*) LLD (No. Detected**) (No. Detected**) (No. Detected**)

Ru-106 (4) -5.3E 0 54 1.9E 1 l.9E 1 (0) -2.1 - 1.0)E 1 1.9 - l.9)E 1 1.9 - 1. 9) E 1 (0/ 2) (0/ 2) (0/ 2)

Ag-108m (4) -1. 2E 0 54 3.5E -1 3.5E -1 (0) -1. 8 - -0.6)E 0 -1.6 - 2.2)E 0 -1.6 - 2.2)E 0 (0/ 2) (0/ 2) (0/ 2)

Ag-110m (4) 2.4E -1 04 2.4E -1 2.3E -1 (0) -1.8 - 2.3)E 0 -1. 8 - 2.3)E 0 -1.9 - 2.4)E 0 (0/ 2) (0/ 2) (0/ 2)

Sb-124 (4) 2.lE 0 04 2.lE 0 -2.4E 0 (0) -3.9 - 8.0)E 0 -3.9 - 8.0)E 0 -9.2 - 4.3)E 0 (0/ 2) (0/ 2) (0/ 2)

Sb-125 (4) 3.2E 0 04 3.2E 0 -5.7E 0 (0) 2.7 - 3.8)E 0 2.7 - 3.8)E 0 -6.0 - -5.4)E 0 (0/ 2) (0/ 2) (0/ 2) 1-131 (4) -1.3E 0 04 -l.3E 0 -2.3E 0 (0) -4.9 - 2.3)E 0 -4.9 - 2.3)E 0 -2.6 - -2.l)E 0 (0/ 2) (0/ 2) (0/ 2)

Cs-134 (4) 130 2.2E 0 54 2.9E 0 2.9E 0 (0) -2.1 - 6.5)E 0 7.6 - 50.4)E -1 7.6 - 50.4)E -1 (0/ 2) (0/ 2) (0/ 2)

Cs-137 (4) 150 2.3E 0 04 2.3E 0 l.2E 0 (0) 1.8 - 2.8)E 0 1.8 - 2.8)E 0 9.7 - 13.8)E -1 (0/ 2) (0/ 2) (0/ 2)

Ba-140 (4) l.9E 1 04 l.9E 1 -2.2E 0 (0) 0.0 - 3.7)E 1 0.0 - 3.7)E 1 -1.9 - 1.5)E 1 (0/ 2) (0/ 2) (0/ 2)

La-140 (4) -3.3E 0 54 l.OE 0 l.OE 0 (0) -7.7 - 1.l)E 0 -2.3 - 4.3)E 0 -2.3 - 4.3)E 0 (0/ 2) (0/ 2) (0/ 2)

Ce-141 (4) -3.2E 0 54 l.OE 0 l.OE 0 (0) -8.7 - 2.3)E 0 -3.1 - 5.l)E 0 -3.1 - 5.l)E 0 (0/ 2) (0/ 2) (0/ 2)

Ce-144 (4) -9.2E -1 04 -9.2E -1 -6.0E 0 (0) -5.1 - 3.3)E 0 -5.1 - 3.3)E 0 -1.2 - O.O)E 1 (0/ 2) (0/ 2) (0/ 2)

Tl-208 (4) -1. 7E 0 54 1.lE 1 l.lE 1 (0) -3.6 - 0.2)E 0 0.0 - 2.l)E 1 0.0 - 2.l)E 1 (0/ 2) (0/ 2) (0/ 2)

Non-Routine refers to those radionuclides that exceeded the Reporting Levels in ODCM Table A.9.1-3.

- The fraction of detectable measurements (i.e., > MDC with no uncertain identification) is shown in parentheses.

Table 3.8-1 (Continued)

Radiological Environmental Monitoring Program Summary Seabrook Nuclear Power Station, Seabrook, NH (January - December 2020)

MEDIUM: American Lobster IHA) UNITS: pCi/kg Indicator Stations Station With Highest Mean Control Stations Radionuclides Mean Station Mean Mean (No. Analyses) Required Range Range Range (Non-Routine*) LLD (No. Detected**) (No. Detected**) (No. Detected**)

Pb-212 (4) -5.7E 0 54 l.lE 0 1.lE 0 (0) -1.4 - 0.2)E 1 -9.5 - 32.5)E -1 -9.5 - 32.5)E -1 (0/ 2) (0/ 2) (0/ 2)

Pb-214 (4) 7.7E 0 04 7.7E 0 -4.3E 0 (0) 3.9 - 11.4)E 0 3.9 - 11.4)E 0 -9.2 - 0.6)E 0 (0/ 2) (0/ 2) (0/ 2)

Bi-214 (4) -2.5E 0 54 4.lE 0 4.lE 0 (0) -5.0 - O.O)E 0 -3.2 - 11.S)E 0 -3.2 - 11.5)E 0 (0/ 2) (0/ 2) (0/ 2)

Ra-226 (4) -2.5E 0 54 4.lE 0 4.lE 0 (0) -5.0 - O.O)E 0 -3.2 - 11.5)E 0 -3.2 - 11.5)E 0 (0/ 2) (0/ 2) (0/ 2)

Ac-228 (4) 7.3E 0 54 4.BE 1 4.BE 1 (0) -5.0 - 19.7)E 0 1.0 - 8.7)E 1 1.0 - 8.7)E 1 (0/ 2) (1/ 2) (1/ 2)

Th-228 (4) -5.7E 0 54 1.lE 0 1.lE 0 (0) -1.4 - 0.2)E 1 -9.5 - 32.5)E -1 -9.5 - 32.5)E -1 (0/ 2) (0/ 2) (0/ 2)

Th-230 (4) -2.5E 0 54 4.lE 0 4.lE 0 (0) -5.0 - O.O)E 0 -3.2 - 11.5)E 0 -3.2 - 11.5)E 0 (0/ 2) (0/ 2) (0/ 2)

Non-Routine refers to those radionuclides that exceeded the Reporting Levels in ODCM Table A.9.1-3.

- The fraction of detectable measurements (i.e., > MDC with no uncertain identification) is shown in parentheses.

3.9 Shellfish Semiannual fish and invertebrate samples are required by the ODCM from two locations. This section provides the results for shellfish (MU) samples only. In 2020, four locations (two indicators and two controls) were included in the sample collections. Fish and lobster results may be found in the Sections 3.7 and 3.8, entitled Fish and Lobsters, respectively.

During the year there were two species of mussels (MU) harvested for analysis. Modiolus (horse mussels) was collected by divers from near the discharge outfall (indicator station MU-06) and from Ipswich Bay (control MU-56). Mytilus (blue mussels) were collected from the intertidal areas of Hampton Harbor (indicator MU-09) and Plum Island (control MU-59). A total of eight samples were collected in 2020 and analyzed for radioactivity in the edible portion or meat of the shellfish.

The only radionuclides detected in edible shellfish body samples in 2020 were naturally-occurring K-40 (all 8 samples), Be-7 (three of 8 samples), Pb-212 (one of 8 samples), Pb-214 (one of 8 samples), and Th-228 (one of 8 samples). Similar to past years, no plant-related gamma emitting radionuclides were detected in any sample. Therefore, no increasing or decreasing trends were observed. Consequently, there is no dose to the public or impact to the environment from this pathway due to plant operations. This is consistent with the pre-operational program and with previous years of plant operations.

Additional analyses were conducted on the May and November shellfish collections from both indicator (MS-

06) and control (MS-56) locations. Mussel shells (MS) were analyzed for Strontium 89 and 90 (four samples) to see if there was any indication of strontium uptake into the shell. For 2020, no Sr-89/90 was detected in any sample. No shell analyses are required by the REMP as defined in the ODCM.

The REMP Summary Table 3.9-1 (mussel bodies) and Table 3.9-2 (mussel shells) list the range of analysis results by radionuclide for Indicator and Control Stations for all shellfish samples. Attachment 1 to this report lists the individual analysis results for each measurement of shellfish under the Sample Type code MU for the edible portions and MS for shells only.

Any sample collection and analysis deviations from the ODCM required program, or reportable concentrations that may have occurred during the year, are described in Section 5.

Table 3.9-1 Radiological Environmental Monitoring Program Summary Seabrook Nuclear Power Station, Seabrook, NH (January - December 2020)

MEDIUM: Mussel Body !MU) UNITS: pCi/kg Indicator Stations Station With Highest Mean Control Stations Radionuclides Mean Station Mean Mean (No. Analyses) Required Range Range Range (Non-Routine*) LLD (No. Detected**) (No. Detected**) (No. Detected**)

Be-7 (8) 3.2E 1 59 2.0E 2 1.3E 2 (0) 1.7 - 4.4)E 1 7.0 - 32.3)E 1 3.8 - 32.3)E 1 (0/ 4) (2/ 2) (3/ 4)

K-40 (8) l.4E 3 09 1.5E 3 1.3E 3 (0) 1.1 - 1. 6)E 3 1.4 - 1.6)E 3 1.1 - 1.5)E 3 (4/ 4) (2/ 2) (4/ 4)

Cr-51 (8) -9.4E 0 56 9.7E 0 -6.5E 0 (0) -1.6 - 0.2)E 1 8.6 - 10.9)E 0 -4.0 - 1.l)E 1 (0/ 4) (0/ 2) (0/ 4)

Mn-54 (8) 130 1. 6E -1 56 1.0E 0 3.8E -1 (0) -1.2 - 2.6)E 0 6.8 - 13.5)E -1 -1.1 - 1.4)E 0 (0/ 4) (0/ 2) (0/ 4)

Co-57 (8) 1.3E 0 59 1.8E 0 1.4E 0 (0) -5.0 - 25.5)E -1 6.2 - 29.5)E -1 -1.1 - 29.5)E -1 (0/ 4) (0/ 2) (0/ 4)

Co-58 (8) 130 -9.7E -1 59 9.3E -1 5.6E -1 (0) -3.2 - 1. 7)E 0 7.9 - 10.7)E -1 -2.9 - 3.3)E 0 (0/ 4) (0/ 2) (0/ 4)

Fe-59 (8) 260 1.5E 0 06 2.lE 0 -1.8E 0 (0) -5.4 - 7.4)E 0 -1.1 - 5.3)E 0 -2.7 - -0.2)E 0 (0/ 4) (0/ 2) (0/ 4)

Co-60 (8) 130 7.9E -2 59 4.8E 0 3.7E 0 (0) -1.3 - 1.3)E 0 -8.9 - 105.0)E -1 -8.9 - 105.0)E -1 (0/ 4) (0/ 2) (0/ 4)

Zn-65 (8) 260 3.lE 0 09 9.2E 0 -3.6E 0 (0) -6.0 - 15.7)E 0 2.6 - 15.7)E 0 -9.0 - 2.0)E 0 (0/ 4) (0/ 2) (0/ 4)

Se-75 (8) 2.lE -1 56 1.9E 0 -4.0E -1 (0) -1.8 - 3.3)E 0 8.3 - 30.6)E -1 -1.1 - 0.6)E 1 (0/ 4) (0/ 2) (0/ 4)

Nb-95 (8) 2.9E 0 09 3.7E 0 -6. 9E -1 (0) -4.5 - 422.0)E -2 3.5 - 3.9)E 0 -3.0 - 2.5)E 0 (0/ 4) (0/ 2) (0/ 4)

Zr-95 (8) 1.7E 0 09 4.0E 0 -2.0E 0 (0) -9.8 - 80.5)E -1 -1.4 - 80.5)E -1 -6.1 - 4.7)E 0 (0/ 4) (0/ 2) (0/ 4)

Ru-103 (8) -3.6E -1 56 5.5E -2 -1.lE 0 (0) -1.4 - 0.6)E 0 -3.2 - 3.3)E 0 -4.5 - 3.3)E 0 (0/ 4) (0/ 2) (0/ 4)

Non-Routine refers to those radionuclides that exceeded the Reporting Levels in ODCM Table A.9.1-3.

- The fraction of detectable measurements (i.e., > MDC with no uncertain identification) is shown in parentheses.

Table 3.9-1 (Continued)

Radiological Environmental Monitoring Program Summary Seabrook Nuclear Power Station, Seabrook, NH (January - December 2020)

MEDIUM: Mussel Body !MU! UNITS: pCi/kg Indicator Stations Station With Highest Mean Control Stations Radionuclides Mean Station Mean Mean (No. Analyses) Required Range Range Range (Non-Routine*) LLD (No. Detected**) (No. Detected**) (No. Detected**)

Ru-106 (8) 1.lE 1 59 l.2E 1 6.lE 0 (0) 8.8 - 12.9)E 0 1.6 - 238.0)E -1 -7.8 - 23.S)E 0 (0/ 4) (0/ 2) (0/ 4)

Ag-108m (8) l.lE 0 06 l.5E 0 7.lE -1 (0) -4.2 - 18.3)E -1 1.2 - 1. 8) E 0 -2.2 - 15.4)E -1 (0/ 4) (0/ 2) (0/ 4)

Ag-110m (8) -3.lE -1 09 1.3E -1 -1. BE 0 (0) -1.2 - 0.5)E 0 -2.3 - 4.9)E -1 -4.1 - O.l)E 0 (0/ 4) (0/ 2) (0/ 4)

Sb-124 (8) 2.0E 0 59 7.9E 0 5.0E 0 (0) 1.1 - 4.8)E 0 4.9 - 10.9)E 0 -1.1 - 10.9)E 0 (0/ 4) (0/ 2) (0/ 4)

Sb-125 (8) -2.3E 0 56 3.4E -1 -2.7E 0 (0) -7.3 - 7.7)E 0 -2.0 - 2.7)E 0 -1.1 - 0.3)E 1 (0/ 4) (0/ 2) (0/ 4) 1-131 (8) -2.4E 0 59 4.0E 0 3.lE 0 (0) -5.2 - -1.0)E 0 1. 6 - 6.4)E 0 -5.0 - 9.3)E 0 (0/ 4) (0/ 2) (0/ 4)

Cs-134 (8) 130 5.7E -1 56 5.7E 0 4.9E 0 (0) -4.7 - 34.6)E -1 4.0 - 7.4)E 0 -1. 8 - 10.2)E 0 (0/ 4) (0/ 2) (0/ 4)

Cs-137 (8) 150 -2.2E 0 59 3.6E 0 9.2E -1 (0) -9.1 - 2.5)E 0 4.6 - 67.6)E -1 -2.8 - 6.B)E 0 (0/ 4) (0/ 2) (0/ 4)

Ba-140 (8) 3.9E 0 56 l.7E 1 9.6E 0 (0) -1.2 - 1.4)E 1 1.1 - 2.3)E 1 -5.6 - 23.4)E 0 (0/ 4) (0/ 2) (0/ 4)

La-140 (8) -1. OE 0 09 1.3E 0 -8.0E 0 (0) -1.1 - 0.9)E 1 -5.9 - 8.6)E 0 -9.7 - -6.l)E 0 (0/ 4) (0/ 2) (0/ 4)

Ce-141 (8) -4.0E 0 56 -4.7E -1 -8.3E -1 (0) -1. 4 - 0.4)E 1 -8.2 - 7.3)E 0 -8.2 - 7.3)E 0 (0/ 4) (0/ 2) (0/ 4)

Ce-144 (8) 2.8E 0 09 8.8E 0 -5.7E 0 (0) -1.1 - 0.9)E 1 8.7 - 8.9)E 0 -1.3 - -0.2)E 1 (0/ 4) (0/ 2) (0/ 4)

Tl-208 (8) 3.7E 0 09 5.2E 0 -1. 4E 0 (0) 1. 7 - 6. 7) E 0 3.8 - 6.7)E 0 -9.3 - 4.6)E 0 (0/ 4) (0/ 2) (0/ 4)

Non-Routine refers to those radionuclides that exceeded the Reporting Levels in ODCM Table A.9.1-3.

- The fraction of detectable measurements (i.e., >MDC with no uncertain identification) is shown in parentheses.

Table 3.9-1 (Continued)

Radiological Environmental Monitoring Program Summary Seabrook Nuclear Power Station, Seabrook, NH (January - December 2020)

MEDIUM: Mussel Body !MU> UNITS: pCi/kg Indicator Stations Station With Highest Mean Control Stations Radionuclides Mean Station Mean Mean (No. Analyses) Required Range Range Range (Non-Routine*) LLD (No. Detected**) (No. Detected**) (No. Detected**)

Pb-212 (8) 4.8E 0 09 1.lE 1 3.lE 0 (0) -5.7 - 21.l)E 0 8.7 - 211.0)E -1 0.0 - 8.2)E 0 (1/ 4) (1/ 2) (0/ 4)

Pb-214 (8) 5.0E 0 56 1.2E 1 5.2E 0 (0) -1. 9 - 20 .1) E 0 1.1 - 1.3)E 1 -8.2 - 12.8)E 0 (1/ 4) (0/ 2) (0/ 4)

Bi-214 (8) 2.8E 0 59 1.2E 1 7.8E 0 (0) -8. 4 - 11. 6) E 0 0.0 - 2.4)E 1 -7.2 - 244.0)E -1 (0/ 4) (0/ 2) (0/ 4)

Ra-226 (8) 2.8E 0 59 1.2E 1 7.8E 0 (0) -8.4 - 11.6)E 0 0.0 - 2.4)E 1 -7.2 - 244.0)E -1 (0/ 4) (0/ 2) (0/ 4)

Ac-228 (8) -6.2E 0 56 1.5E 1 -4.7E 0 (0) -4.8 - 1.0)E 1 -5.8 - 36.0)E 0 -3. 9 - 3. 6) E 1 (0/ 4) (0/ 2) (0/ 4)

Th-228 (8) 4.8E 0 09 1.lE 1 3.lE 0 (0) -5.7 - 21.l)E 0 8.7 - 211.0)E -1 0.0 - 8.2)E 0 (1/ 4) (1/ 2) (0/ 4)

Th-230 (8) 2.8E 0 59 1.2E 1 7.8E 0 (0) -8.4 - 11.6)E 0 0.0 - 2.4)E 1 -7.2 - 244.0)E -1 (0/ 4) (0/ 2) (0/ 4)

Non-Routine refers to those radionuclides that exceeded the Reporting Levels in ODCM Table A.9.1-3.

- The fraction of detectable measurements (i.e., >MDC with no uncertain identification) is shown in parentheses.

Table 3.9-2 Radiological Environmental Monitoring Program Summary Seabrook Nuclear Power Station, Seabrook, NH (January - December 2020)

MEDIUM: Mussel Shell (MSl UNITS: pCi/kg Indicator Stations Station With Highest Mean Control Stations Radionuclides Mean Station Mean Mean (No. Analyses) Required Range Range Range (Non-Routine*) LLD (No. Detected**) (No. Detected**) (No. Detected**)

Sr-89 (4) 300 -6.2E 1 56 -5.2E 1 -5.2E 1 (0) -1.1 - -0.l)E 2 -1.1 - O.l)E 2 -1.1 - 0 .l)E 2 (0/ 2) (0/ 2) (0/ 2)

Sr-90 (4) 300 -8.4E 1 56 2. 7E 1 2.7E 1 (0) -1.3 - -0.4)E 2 -1.3 - 6.7)E 1 -1.3 - 6.7)E 1 (0/ 2) (0/ 2) (0/ 2)

Non-Routine refers to those radionuclides that exceeded the Reporting Levels in ODCM Table A.9.1-3.

- The fraction of detectable measurements (i.e., >MDC with no uncertain identification) is shown in parentheses.

3.10 Irish Moss There is no REMP technical requirement defined in the ODCM to collect Irish Moss (algae) samples. As a supplement to the required REMP, semiannual Chondrus (Irish Moss) samples were collected from an indicator area (AL-05) near the plant discharge and a control location (AL-55) within Ipswich Bay. If plant-related radionuclides were re-concentrating in the aquatic environment, an early indication of this might be shown in this type of environmental species. Four routine samples (two indicators and two controls) were collected for the year.

A gamma analysis was performed on each sample. Although not required by Table 5.2-1, the LLDs associated with food products were applied to ensure adequate counting statistics. Naturally-occurring K-40 was detected in two indicator samples, and K-40 and Be-7 were detected in two control samples. For the off-shore indicator station (AL-05), no plant-related radionuclides were detected in any sample.

Therefore, no plant-related increasing or decreasing trends were observed. Subsequently, there is no dose or impact to the environment from plant operations. This is consistent with the pre-operational program and previous years of plant operations.

The REMP Summary Table 3.10-1 lists the range of analysis results by radionuclide for Indicator and Control Stations for Irish Moss samples. Attachment 1 lists the individual analysis results for each measurement of Irish moss under the Sample Type code AL.

Any sample collection and analysis deviations from the ODCM defined program, or reportable concentrations that may have occurred during the year, are described in Section 5.

Table 3.10-1 Radiological Environmental Monitoring Program Summary Seabrook Nuclear Power Station, Seabrook, NH (January - December 2020)

MEDIUM: Irish Moss (All UNITS: pCi/kg Indicator Stations Station With Highest Mean Control Stations Radionuclides Mean Station Mean Mean (No. Analyses) Required Range Range Range (Non-Routine*) LLD (No. Detected**) (No. Detected**) (No. Detected**)

Be-7 (4) 3.0E 1 55 1.9E 2 1.9E 2 (0) 0.0 - 6.l)E 1 9.5 - 27.6)E 1 9.5 - 27.6)E 1 (0/ 2) (2/ 2) (2/ 2)

K-40 (4) 7.6E 3 05 7.6E 3 6.5E 3 (0) 7.4 - 7.8)E 3 7.4 - 7.8)E 3 4.9 - 8.0)E 3 (2/ 2) (2/ 2) (2/ 2)

Cr-51 (4) 1. 6E 1 05 1.6E 1 -3.9E 1 (0) 0.0 - 3.3)E 1 0.0 - 3.3)E 1 -4.0 - -3.7)E 1 (0/ 2) (0/ 2) (0/ 2)

Mn-54 (4) -3.4E 0 55 1.lE 0 1.lE 0 (0) -3.9 - -3.0)E 0 -4.6 - 6.7)E 0 -4.6 - 6.7)E 0 (0/ 2) (0/ 2) (0/ 2)

Co-57 (4) 2.4E 0 05 2.4E 0 1.9E 0 (0) 8.2 - 39.6)E -1 8.2 - 39.6)E -1 -7.1 - 45.7)E -1 (0/ 2) (0/ 2) (0/ 2)

Co-58 (4) -2.lE 0 05 -2.lE 0 -6.2E 0 (0) -8.5 - 4.3)E 0 -8.5 - 4.3)E 0 -7.7 - -4.8)E 0 (0/ 2) (0/ 2) (0/ 2)

Fe-59 (4) -4.8E 0 55 7.2E 0 7.2E 0 (0) -6.2 - -3.4)E 0 5.9 - 8.4)E 0 5.9 - 8.4)E 0 (0/ 2) (0/ 2) (0/ 2)

Co-60 (4) -2.5E 0 55 l.4E 0 l.4E 0 (0) -7.2 - 2.l)E 0 -2.3 - 30.5)E -1 -2.3 - 30.5)E -1 (0/ 2) (0/ 2) (0/ 2)

Zn-65 (4) 1.4E 1 05 1.4E 1 4.6E 0 (0) 1.9 - 25.9)E 0 1. 9 - 25. 9) E 0 4.4 - 4.9)E 0 (0/ 2) (0/ 2) (0/ 2)

Se-75 (4) -5.7E -1 55 4.8E 0 4.8E 0 (0) -2 .4 - 1.3)E 0 1. 7 - 7. 9)E 0 1.7 - 7.9)E 0 (0/ 2) (0/ 2) (0/ 2)

Nb-95 (4) 5.4E 0 05 5.4E 0 7.5E -1 (0) -4.8 - 15.5)E 0 -4.8 - 15.5)E 0 -1.5 - 3.0)E 0 (0/ 2) (0/ 2) (0/ 2)

Zr-95 (4) -4.2E 0 55 -1.lE 0 -1.lE 0 (0) -7.8 - -0.5)E 0 -1.4 - -0.9)E 0 -1.4 - -0.9)E 0 (0/ 2) (0/ 2) (0/ 2)

Ru-103 (4) -1.5E 0 55 -5.6E -1 -5.6E -1 (0) -6.1 - 3.0)E 0 -3.4 - 2.3)E 0 -3.4 - 2.3)E 0 (0/ 2) (0/ 2) (0/ 2)

Non-Routine refers to those radionuclides that exceeded the Reporting Levels in ODCM Table A.9.1-3.

- The fraction of detectable measurements (i.e., >MDC with no uncertain identification) is shown in parentheses.

Table 3.10-1 Radiological Environmental Monitoring Program Summary Seabrook Nuclear Power Station, Seabrook, NH (January - December 2020)

MEDIUM: Irish Moss !All UNITS: pCi/kg Indicator Stations Station With Highest Mean Control Stations Radionuclides Mean Station Mean Mean (No. Analyses) Required Range Range Range (Non-Routine*) LLD (No. Detected**) (No. Detected**) (No. Detected**)

Ru-106 (4) -2.6E 0 55 1.5E 1 1.5E 1 (0) -4.B - -0.5)E 0 1.2 - 1. 9) E 1 1.2 - 1. 9) E 1 (0/ 2) (0/ 2) (0/ 2)

Ag-108m (4) -4.3E 0 55 -1.2E 0 -1.2E 0 (0) -5.6 - -2.9)E 0 -2.B - 0.3)E 0 -2.B - 0.3)E 0 (0/ 2) (0/ 2) (0/ 2)

Ag-110m (4) -6.7E 0 55 3.0E 0 3.0E 0 (0) -1.1 - -0.3)E 1 -3.7 - 601.0)E -2 -3.7 - 601. 0) E -2 (0/ 2) (0/ 2) (0/ 2)

Sb-124 (4) 1.2E 0 05 l.2E 0 -6. 4E 0 (0) -1. 4 - 1. 6) E 1 -1. 4 - 1. 6) E 1 -1.3 - O.O)E 1 (0/ 2) (0/ 2) (0/ 2)

Sb-125 (4) 2.5E 0 05 2.5E 0 -B.9E 0 (0) -1. B - 52.7)E -1 -1. B - 52.7)E -1 -9.4 - -B.5)E 0 (0/ 2) (0/ 2) (0/ 2) 1-131 (4) 60 2.2E 0 55 6.4E 0 6.4E 0 (0) 1. 6 - 2. 9) E 0 3.6 - 9.2)E 0 3.6 - 9.2)E 0 (0/ 2) (0/ 2) (0/ 2)

Cs-134 (4) 60 1.5E -2 05 1.5E -2 -1.BE 0 (0) -1. 9 - 1. 9) E 0 -1.9 - 1. 9) E 0 -2.3 - -1.3)E 0 (0/ 2) (0/ 2) (0/ 2)

Cs-137 (4) BO 4.3E 0 05 4.3E 0 -5.4E 0 (0) -4.4 - 90.5)E -1 -4.4 - 90.5)E -1 -1.2 - 0.2)E 1 (0/ 2) (0/ 2) (0/ 2)

Ba-140 (4) 3.4E 1 05 3.4E 1 2.lE 0 (0) 9.3 - 5B.4)E 0 9.3 - 5B.4)E 0 -7.5 - 11.7)E 0 (0/ 2) (0/ 2) (0/ 2)

La-140 (4) -1. BE 0 05 -1. BE 0 -7. 9E 0 (0) -3.9 - 0.4)E 0 -3.9 - 0.4)E 0 -1.3 - -0.2)E 1 (0/ 2) (0/ 2) (0/ 2)

Ce-141 (4) 2.lE -1 55 4.lE 0 4.lE 0 (0) -1.5 - 1.9)E 0 3.2 - 4.9)E 0 3.2 - 4.9)E 0 (0/ 2) (0/ 2) (0/ 2)

Non-Routine refers to those radionuclides that exceeded the Reporting Levels in ODCM Table A.9.1-3.

- The fraction of detectable measurements (i.e., > MDC with no uncertain identification) is shown in parentheses.

Table 3.10-1 Radiological Environmental Monitoring Program Summary Seabrook Nuclear Power Station, Seabrook, NH (January - December 2020)

MEDIUM: Irish Moss !All UNITS: pCi/kg Indicator Stations Station With Highest Mean Control Stations Radionuclides Mean Station Mean Mean (No. Analyses) Required Range Range Range (Non-Routine*) LLD (No. Detected**) (No. Detected**) (No. Detected**)

Ce-144 (4) l.SE 1 05 l.SE 1 -7.3E 0 (0) -1. 4 - 4.3)E 1 -1.4 - 4.3)E 1 -1.8 - 0 .3)E 1 (0/ 2) (0/ 2) (0/ 2)

Ac-228 (4) l.3E 1 55 5.3E 1 5.3E 1 (0) 6.3 - 19.8)E 0 2.8 - 7.9)E 1 2.8 - 7.9)E 1 (0/ 2) (0/ 2) (0/ 2)

Th-228 (4) 7.3E 0 05 7.3E 0 4.6E 0 (0) -4.8 - 19.4)E 0 -4.8 - 19.4)E 0 4.1 - 5.l)E 0 (0/ 2) (0/ 2) (0/ 2)

Non-Routine refers to those radionuclides that exceeded the Reporting Levels in ODCM Table A.9.1-3.

- The fraction of detectable measurements (i.e., > MDC with no uncertain identification) is shown in parentheses.

3.11 Food Crop There is no requirement for food crop or vegetation samples as long as the required milk locations are available. As noted in Section 3.3, milk sampling at the minimum required number of locations in 2020 was not possible due to the limited inventory of milk animal sites in the plant vicinity. To compensate for this, vegetation samples were collected as part of the REMP. Section 3.12 describes the alternate broad leafy vegetation (TG) collections.

In addition to the broad leafy vegetation sampling, nine food crop (TF) samples were collected from three locations listed on Table 2.0-2 (two indicator stations, TF-02 and TF-03, and one control station, TF-06) during the growing season months (June, July and August). These included strawberries in June (Lab numbers 514168001, 2, & 3), blueberries and squash in July (Lab numbers 516040001, 2, & 3), and tomatoes in August (Lab numbers 518831001, 2 and 3).

A gamma analysis was performed on each sample. Naturally-occurring K-40 was detected in all samples for both indicator and control stations. Similar to past years, no plant-related radionuclides were detected in any samples. Therefore, no increasing or decreasing trends are identified. Subsequently, there is no dose to the public or impact on the environment through this pathway due to plant operations. This is consistent with the pre-operational program and with previous years of plant operations.

The following REMP Summary (Table 3.11-1) lists the range of analysis results by radionuclide for indicator and control stations for the Food Crop environmental media. Attachment 1 to this report lists the individual analysis results for each measurement of Food Crops under the Sample Type code TF.

Any sample collection and analysis deviations from the ODCM defined program, or reportable concentrations that may have occurred during the year, are described in Section 5.

Table 3.11-1 Radiological Environmental Monitoring Program Summary Seabrook Nuclear Power Station, Seabrook, NH (January - December 2020)

MEDIUM: Food Crop !TFl UNITS: pCi/kg Indicator Stations Station With Highest Mean Control Stations Radionuclides Mean Station Mean Mean (No. Analyses) Required Range Range Range (Non-Routine*) LLD (No. Detected**) (No. Detected**) (No. Detected**)

Be-7 (9) l.2E 1 03 2.lE 1 1.7E 1 (0) -2.0 - 2.8)E 1 1.3 - 2.8)E 1 1.1 - 2.3)E 1 (0/ 6) (0/ 3) (0/ 3)

K-40 (9) 1. 7E 3 03 2.lE 3 1.3E 3 (0) 6.2 - 25.8)E 2 1.5 - 2.6)E 3 4. 9 - 21. 6) E 2 (6/ 6) (3/ 3) (3/ 3)

Cr-51 (9) 9.2E 0 03 1.lE 1 8.3E 0 (0) -3.1 - 23.4)E 0 7.0 - 234.0)E -1 -1. 2 - 24. 6) E 0 (0/ 6) (0/ 3) (0/ 3)

Mn-54 (9) 9.2E -1 03 1.5E 0 -2.2E -1 (0) -1.3 - 4.3)E 0 -2.4 - 42.5)E -1 -4.7 - 2.5)E 0 (0/ 6) (0/ 3) (0/ 3)

Co-57 (9) 4 .lE -1 06 8.7E -1 8.7E -1 (0) -1.1 - 2.l)E 0 2.8 - 13.9)E -1 2.8 - 13.9)E -1 (0/ 6) (0/ 3) (0/ 3)

Co-58 (9) -6.lE -1 06 l.8E 0 1.8E 0 (0) -2.2 - 1.5)E 0 -6.6 - 62.6)E -1 -6.6 - 62.6)E -1 (0/ 6) (0/ 3) (0/ 3)

Fe-59 (9) 1. OE 0 02 5.3E 0 -2.6E 0 (0) -9.9 - 8.3)E 0 3.7 - 8.3)E 0 -7.8 - 2.l)E 0 (0/ 6) (0/ 3) (0/ 3)

Co-60 (9) 4 .lE -1 02 4.4E -1 1. 6E -1 (0) -4.0 - 11.3)E -1 -4.0 - 11.3)E -1 -2.1 - 3.0)E 0 (0/ 6) (0/ 3) (0/ 3)

Zn-65 (9) 8.0E -1 02 1.4E 0 -8.6E -1 (0) -4.7 - 7.0)E 0 -4.7 - 7.0)E 0 -2.1 - 0.7)E 0 (0/ 6) (0/ 3) (0/ 3)

Se-75 (9) 6.0E -1 03 1.9E 0 -5.5E -1 (0) -7.0 - 31.2)E -1 6.6 - 31.2)E -1 -1.6 - 0.5)E 0 (0/ 6) (0/ 3) (0/ 3)

Nb-95 (9) 2.3E 0 02 3.0E 0 -9.5E -2 (0) 6.9 - 50.2)E -1 7.5 - 50.2)E -1 -2.0 - 2.3)E 0 (0/ 6) (0/ 3) (0/ 3)

Zr-95 (9) 5. 4E -1 06 l.2E 0 1.2E 0 (0) -6.7 - 21.3)E -1 1.5 - 339.0)E -2 1.5 - 339.0)E -2 (0/ 6) (0/ 3) (0/ 3)

Ru-103 (9) -1. 4E 0 06 1.2E 0 1.2E 0 (0) -4.3 - 1.7)E 0 -6.0 - 43.l)E -1 -6.0 - 43.l)E -1 (0/ 6) (0/ 3) (0/ 3)

Non-Routine refers to those radionuclides that exceeded the Reporting Levels in ODCM Table A.9.1-3.

- The fraction of detectable measurements (i.e., > MDC with no uncertain identification) is shown in parentheses.

Table 3.11-1 (Continued)

Radiological Environmental Monitoring Program Summary Seabrook Nuclear Power Station, Seabrook, NH (January - December 2020)

MEDIUM: Food Crop !TFl UNITS: pCi/kg Indicator Stations Station With Highest Mean Control Stations Radionuclides Mean Station Mean Mean (No. Analyses) Required Range Range Range (Non-Routine*) LLD (No. Detected**) (No. Detected**) (No. Detected**)

Ru-106 (9) -1.4E 1 06 3.3E 0 3.3E 0 (0) -3.1 - 0.6)E 1 -2.1 - 5.l)E 1 -2.1 - 5.l)E 1 (0/ 6) (0/ 3) (0/ 3)

Ag-108m (9) 1.8E -2 03 8.5E -1 -1. 7E 0 (0) -4.0 - 1.3)E 0 4.2 - 12.5)E -1 -2.5 - -1.3)E 0 (0/ 6) (0/ 3) (0/ 3)

Ag-110m (9) -8.0E -1 03 4.lE -1 -3.3E -1 (0) -4.9 - 1.2)E 0 -7.2 - 12.2)E -1 -2.4 - 1.8)E 0 (0/ 6) (0/ 3) (0/ 3)

Sb-124 (9) -2.6E -1 03 3.3E 0 -2.4E 0 (0) -1.1 - 0.6)E 1 1.8 - 6.l)E 0 -5.1 - -0.9)E 0 (0/ 6) (0/ 3) (0/ 3)

Sb-125 (9) -2.lE 0 06 1.6E 0 l.6E 0 (0) -1.5 - 0.2)E 1 -1.1 - 4.7)E 0 -1.1 - 4.7)E 0 (0/ 6) (0/ 3) (0/ 3) 1-131 (9) 60 5.4E -1 02 2.3E 0 1.5E 0 (0) -4.2 - 9.2)E 0 -4.2 - 9.2)E 0 6.0 - 25.8)E -1 (0/ 6) (0/ 3) (0/ 3)

Cs-134 (9) 60 1.2E 0 03 1.4E 0 -1.0E 0 (0) -1.8 - 31.0)E -1 2.4 - 31.0)E -1 -4.9 - 2.5)E 0 (0/ 6) (0/ 3) (0/ 3)

Cs-137 (9) 80 2.3E 0 02 2.3E 0 5.8E -1 (0) -4.4 - 59.3)E -1 -4.4 - 59.3)E -1 -1.3 - 2.8)E 0 (0/ 6) (0/ 3) (0/ 3)

Ba-140 (9) 6.3E -1 06 3.8E 0 3.8E 0 (0) -6.9 - 13.4)E 0 -2.7 - 10.3)E 0 -2.7 - 10.3)E 0 (0/ 6) (0/ 3) (0/ 3)

La-140 (9) -2.2E 0 06 -1.lE 0 -1.lE 0 (0) -6.1 - 1.2)E 0 -1.7 - O.O)E 0 -1. 7 - O.O)E 0 (0/ 6) (0/ 3) (0/ 3)

Ce-141 (9) -1.8E 0 06 4.4E -1 4.4E -1 (0) -5.4 - 1.9)E 0 -8.2 - 14.5)E -1 -8.2 - 14.5)E -1 (0/ 6) (0/ 3) (0/ 3)

Ce-144 (9) 5.lE 0 03 7.2E 0 -2.3E 0 (0) -5.3 - 13.0)E 0 4.2 - 11.l)E 0 -2.0 - 1.4)E 1 (0/ 6) (0/ 3) (0/ 3)

Ac-228 (9) 4.9E 0 02 1.3E 1 1.2E 1 (0) -6.4 - 25.3)E 0 5.0 - 25.3)E 0 6.1 - 17.7)E 0 (0/ 6) (0/ 3) (0/ 3)

Th-228 (9) -1.3E 0 06 3.0E 0 3.0E 0 (0) -9.7 - 5.l)E 0 -3.6 - 8.3)E 0 -3.6 - 8.3)E 0 (0/ 6) (0/ 3) (0/ 3)

Non-Routine refers to those radionuclides that exceeded the Reporting Levels in ODCM Table A.9.1-3.

- The fraction of detectable measurements (i.e., > MDC with no uncertain identification) is shown in parentheses.

3.12 Vegetation In lieu of milk sampling, the ODCM, Table A.9.1-1, requires that broad leafy vegetation (TG) samples grown in the nearest of two different offsite locations with the highest D/Q, and from one control location 15-30 km distant in the least prevalent wind direction, be collected when available (growing season).

Offsite locations are defined in the UFSAR as the land beyond a 3000-foot radius of the two Containment Building centerlines. The analysis of garden locations in the Land Use Census provides a ranking of potential sampling sites for use in determining sampling locations in the general population. Since sampling of broad leaf garden vegetables at high D/Q locations is not feasible due to uncertain availability, other types of broad leafy vegetation were utilized.

Two locations at the site boundary with a maximum D/Q (higher values than determined in the 2020 Land Use Census garden listing) were selected over ranked D/Q gardens in the general population. These two Indicator locations (TG-08 and TG-09) are on site property in areas with available sample media. A third far-field control location (TG-10) was selected in Georgetown, MA. Samples consisted of tree leaves, as broad leaf vegetation provides increased reliability for sample availability. For 2020, a total of 18 monthly (growing season) broad leaf vegetation samples were collected and analyzed by gamma spectroscopy.

A gamma analysis was performed on each sample. Naturally-occurring Be-7 was detected in all samples for both indicator and control stations and K-40 was detected in 17 of 18 samples. Naturally-occurring Ac-228, part of the Thorium-232 decay chain, was detected in two samples. Naturally-occurring Th-228, part of the Thorium-232 decay chain, was detected in one of 18 samples. Cesium-137 was not detected in 2020, but has been detected in broad leafy vegetation in past and evaluated as to the source. The conclusion of the assessment was that world-wide fallout from events un-related to Seabrook operations, such as the March 11, 2011 Fukushima Daiichi accident in Japan and past atmospheric nuclear weapons testing, have led to Cs-137 being deposited on the ground surface in the northeast United States with subsequent root uptake into leaves of long-lived vegetation. This conclusion continues to be supported by the fact that Seabrook Station had no detectable Cs-137 in any gaseous effluents in recent years, including 2020, and by the prevalence of detectable Cs-137 at the control location compared to in-close indicator sampling points. Utilizing the results of broad leaf vegetation sampling for broad leaf food products, it is concluded that there was no dose impact to the public or to the environment through this food ingestion pathway from Seabrook plant operations.

The following REMP Summary (Table 3.12-1) lists the range of analysis results by radionuclide for indicator and control stations for the broad leaf vegetation environmental media. Attachment 1 to this report lists the individual analysis results for each measurement of broad leaf vegetation under the Sample Type code TG.

Any sample collection and analysis deviations from the ODCM required program, or reportable concentrations that may have occurred during the year, are described in Section 5.

Table 3.12-1 Radiological Environmental Monitoring Program Summary Seabrook Nuclear Power Station, Seabrook, NH (January - December 2020)

MEDIUM: Vegetation <TGl UNITS: pCi/kg Indicator Stations Station With Highest Mean Control Stations Radionuclides Mean Station Mean Mean (No. Analyses) Required Range Range Range (Non-Routine*) LLD (No. Detected**) (No. Detected**) (No. Detected**)

Be-7 (18) 7.8E 2 08 7.9E 2 7.7E 2 (0) 1.6 - 14.3)E 2 2.4 - 13.l)E 2 3.4 - 11.l)E 2 (12/ 12) (6/ 6) (6/ 6)

K-40 (18) 3.6E 3 10 4.0E 3 4.0E 3 (0) 0.0 - 5.4)E 3 2.4 - 5.2)E 3 2.4 - 5.2)E 3 (11/ 12) (6/ 6) (6/ 6)

Cr-51 (18) -1. 7E 1 10 -2.3E 0 -2.3E 0 (0) -9.0 - 4.l)E 1 -8.5 - 5.9)E 1 -8.5 - 5.9)E 1 (0/ 12) (0/ 6) (0/ 6)

Mn-54 (18) 1.8E 0 08 2.3E 0 -8.3E -3 (0) -3.7 - 9.9)E 0 -3.4 - 9.9)E 0 -7.7 - 11.5)E 0 (0/ 12) (0/ 6) (0/ 6)

Co-57 (18) 2.7E 0 09 4.9E 0 2.6E 0 (0) -7.8 - 14.3)E 0 -1.1 - 143.0)E -1 2.2 - 523.0)E -2 (0/ 12) (0/ 6) (0/ 6)

Co-58 (18) 7.9E -2 10 5.0E 0 5.0E 0 (0) -1.3 - 1.2)E 1 -3.8 - 10.0)E 0 -3.8 - 10.0)E 0 (0/ 12) (0/ 6) (0/ 6)

Fe-59 (18) 5.6E 0 08 6.lE 0 -2.9E 0 (0) -8.3 - 26.3)E 0 6.1 - 187.0)E -1 -1.3 - 0.5)E 1 (0/ 12) (0/ 6) (0/ 6)

Co-60 (18) 3.2E 0 09 3.7E 0 4.8E -1 (0) -1.3 - 2.7)E 1 -6.5 - 11. 6)E 0 -8.4 - 10.0)E 0 (0/ 12) (0/ 6) (0/ 6)

Zn-65 (18) 7.9E 0 08 1.2E 1 -4.5E -1 (0) -9.9 - 50.7)E 0 -9.9 - 50.7)E 0 -2.3 - 1.9)E 1 (0/ 12) (0/ 6) (0/ 6)

Se-75 (18) 4.5E -1 08 5.lE 0 -5.lE 0 (0) -1.7 - 1.6)E 1 -3.9 - 15.7)E 0 -1.3 - 0.3)E 1 (0/ 12) (0/ 6) (0/ 6)

Nb-95 (18) 1.5E 0 09 1.5E 0 2.0E -1 (0) -6.9 - 9.l)E 0 -6.9 - 9.l)E 0 -3.4 - 6.2)E 0 (0/ 12) (0/ 6) (0/ 6)

Zr-95 (18) -2.9E -1 10 1.3E 0 1.3E 0 (0) -1.7 - 2.5)E 1 -9.0 - 12.3)E 0 -9.0 - 12.3)E 0 (0/ 12) (0/ 6) (0/ 6)

Ru-103 (18) 1.lE 0 09 2.6E 0 -4.2E 0 (0) -1.1 - 1.6)E 1 -4.2 - 16.4)E 0 -9.4 - 2.9)E 0 (0/ 12) (0/ 6) (0/ 6)

Ru-106 (18) -4.3E -1 10 5.3E 1 5.3E 1 (0) -1.4 - 1. 9)E 2 -1.5 - 12.l)E 1 -1.5 - 12.l)E 1 (0/ 12) (0/ 6) (0/ 6)

Non-Routine refers to those radionuclides that exceeded the Reporting Levels in ODCM Table A.9.1-3.

- The fraction of detectable measurements (i.e., > MDC with no uncertain identification) is shown in parentheses.

Table 3.12-1 (Continued)

Radiological Environmental Monitoring Program Summary Seabrook Nuclear Power Station, Seabrook, NH (January - December 2020)

MEDIUM: Vegetation !TGl UNITS: pCi/kg Indicator Stations Station With Highest Mean Control Stations Radionuclides Mean Station Mean Mean (No. Analyses) Required Range Range Range (Non-Routine*) LLD (No. Detected**) (No. Detected**) (No. Detected**)

Ag-108m (18) -4.2E -1 10 1.3E -1 1.3E -1 (0) -1.0 - 1.2)E 1 -4.3 - 4.0)E 0 -4.3 - 4.0)E 0 (0/ 12) (0/ 6) (0/ 6)

Ag-110m (18) -2.3E 0 10 1.6E 0 1.6E 0 (0) -2.4 - 1.5)E 1 -7.1 - 8.5)E 0 -7.1 - 8.5)E 0 (0/ 12) (0/ 6) (0/ 6)

Sb-124 (18) -2.7E 0 09 2.8E 0 -5.3E 0 (0) -2.3 - 1.9)E 1 -6.0 - 18.7)E 0 -3.3 - 0.9)E 1 (0/ 12) (0/ 6) (0/ 6)

Sb-125 (18) 4.3E 0 09 1.0E 1 4.7E 0 (0) -2.0 - 4.9)E 1 -1.7 - 4.9)E 1 -4.3 - 18.8)E 0 (0/ 12) (0/ 6) (0/ 6) 1-131 (18) 60 6.3E -1 09 4.5E 0 -3.5E 0 (0) -1.2 - 1.0)E 1 -3.2 - 10.3)E 0 -2.0 - 0.4)E 1 (0/ 12) (0/ 6) (0/ 6)

Cs-134 (18) 60 8.lE -1 08 6.lE 0 2.4E 0 (0) -1.3 - 2.3)E 1 -3.6 - 23.4)E 0 -2.7 - 6.7)E 0 (0/ 12) (0/ 6) (0/ 6)

Cs-137 (18) 80 3.8E 0 09 4.2E 0 1. 9E 0 (0) -6.8 - 21.4)E 0 -8.0 - 101.0)E -1 -9.3 - 13.3)E 0 (0/ 12) (0/ 6) (0/ 6)

Ba-140 (18) 1.6E 0 08 1.2E 1 -2.lE 1 (0) -6.1 - 3.4)E 1 -1. 7 - 3.4)E 1 -9.4 - 1.2)E 1 (0/ 12) (0/ 6) (0/ 6)

La-140 (18) -3.8E 0 09 -2.lE -1 -1. 7E 0 (0) -1.7 - 0.9)E 1 -1.5 - 0.9)E 1 -8.2 - 11.0)E 0 (0/ 12) (0/ 6) (0/ 6)

Ce-141 (18) -1.5E 1 10 -6.2E 0 -6.2E 0 (0) -6.1 - 1.0)E 1 -2.0 - 0.9)E 1 -2.0 - 0.9)E 1 (0/ 12) (0/ 6) (0/ 6)

Ce-144 (18) -4. 9E 0 08 7.6E 0 -1. 6E 1 (0) -1.2 - 0.4)E 2 -4.2 - 3.8)E 1 -4.3 - 0.6)E 1 (0/ 12) (0/ 6) (0/ 6)

Ac-228 (18) 5.2E 1 09 7.0E 1 6.3E 1 (0) -1.6 - 17.l)E 1 1.1 - 17 .1) E 1 -8.6 - 135.0)E 0 (1/ 12) (1/ 6) (1/ 6)

Th-228 (18) 1.lE 1 08 1.8E 1 6.lE 0 (0) -2.1 - 7.9)E 1 -2.1 - 7.9)E 1 -2.4 - 2.6)E 1 (1/ 12) (1/ 6) (0/ 6)

Non-Routine refers to those radionuclides that exceeded the Reporting Levels in ODCM Table A.9.1-3.

- The fraction of detectable measurements (i.e., >MDC with no uncertain identification) is shown in parentheses.

3.13 Direct Radiation Direct gamma radiation exposure was measured with thermoluminescent dosimeters (TLDs). Two TLD badges are placed at each of the designated monitoring stations. Each TLD badge has three CaS0 4 :Tm elements. The badges were collected and read on a quarterly schedule. A location result is an average of six independent readings per quarter. A total of forty-six stations are located offsite, forty of which are required by the ODCM.

The exposure rates were normalized to a standard 91-day quarter so that quarterly results from any monitoring location can be compared to another location based on an equivalent time period of exposure.

A summary of the 2020 data for the plant operational REMP is shown in Table 3.13-1. Figures 3.6 through 3.14 provide a comparison of quarterly TLD location responses in 2020 and illustrate the naturally variation in exposure rates quarter to quarter. Figures 3.6.1 through 3.14.1 provide a long term trend line for each of the environmental TLD locations.

The exposure rate response at individual monitoring stations have on occasion exhibited step changes at some point in the past that are related to changes in local conditions in the area of the dosimeter measurement. As an example, the outer ring TL-33 (a parking lot located 9.8 km south of the plant) was observed for several quarters in the recent past to approach or exceed the normal expected environmental fluctuations based on observed history. The average TLD exposure rate from the 2nd quarter 2011 through the 4th quarter of 2013 is reported as 21.8 mR/quarter. For the seven prior quarters (3rd quarter 2009 to the 1st quarter 2011 ), the average TLD response was 18.6 mR/quarter, or approximately 17% lower than the most recent trend history. Since no other TLDs in the same sector or closer to the plant showed an average increase in measured response above the expected, the change at TL-33 was attributed to a local change in the background radiation associated with parking lot modifications and not with Seabrook Station operations. Field investigations of TL-33 indicated that the parking lot appeared to be re-graded with new fill/gravel material which could have increased the natural concentration of background radiation that the TLD measures. The expected background exposure level for location TL-33 was re-indexed to 20.6 mR/quarter in 2013 to reflect the observed change in background radiation. Three other locations (TL-01, TL-69 and TL-18) also indicated changes in background exposure rates trends over time (un-related to Seabrook operations) and had their expected background exposure levels re-indexed to 17.4 mR/quarter, 13.7 mR/quarter, and 16.3 mR/quarter respectively, in 2013 (for TL-01 and TL-69) and 2019 (for TL-18).

Overall, the REMP direct radiation program showed no statistically significant indication of increased direct radiation above the variable background measured exposure rate in unrestricted areas. This is demonstrated by the fact that indicator location results (as a group) are statistically the same as control locations. The 2020 annual mean of all indicator locations was 16.5 mR/91-day quarter while the mean of all control locations was 17.4 mR/91-day quarter. This indicates that collectively there is no statistical difference in the annual direct dose as a function of distance from the plant. As a result, no direct radiation dose beyond the site boundary was attributed to station operation during 2020.

Starting in 2015, a supplemental analytical method was implemented to evaluate the TLD measurements.

Using the method described in ANSl/HPS N13.37-2014, quarterly and annual baseline dose for each TLD location was determined using appropriate statistical analytical methods considering data from 2004 through 2014. Quarterly and annual dose for 2020 was compared to baseline values to determine if an Investigation Level had been exceeded for evaluation of potential dose to a member of the public. An Investigation Level is considered to be exceeded under the following conditions:

Quarterly: If M0 > (Ba + MDD0 ), then Fa =M 0 - Ba Where:

M0 is the normalized quarterly field measurement result Ba is the quarterly baseline background dose MDDa is the quarterly minimum differential dose and Fa is the quarterly facility related dose Or: Annually: If MA > (BA+ MDDA), then FA= MA - BA Where:

MA is the sum of the four normalized quarterly measurement values BA is the annual baseline background dose MDDA is the annual minimum differential dose FA is the annual facility related dose Table 3.13-3 summarizes the evaluation of the TLD measurements using the methodology described in ANSl/HPS N13.37-2014. As noted in Table 3.13-3, an annual dose of 14.6 mR was calculated for location TL-25 using the ANSl/HPS N13.37-2014 methodology and the baseline values calculated using data from 2004 to 2014. However, this dose was determined not to be facility related due to the distance of this TLD location with respect to the plant (7.6 km) and the lack of any observed dose for TLD locations closer to the plant. The observed dose is likely a result of a change in the environment at the TLD location. Figure 3.10.1 shows a step increase in the quarterly TLD values for this location starting in 2020.

For this reason, the location will continue to be monitored and the quarterly and annual baseline values for this location will be adjusted, as necessary.

The direct radiation-monitoring program demonstrated that no increasing or decreasing trends were detected. Therefore, there was no offsite dose to the public or impact to the environment from the operation of the plant.

Any TLD collection and analysis deviations from the ODCM required program that may have occurred during the year are described in Section 5.

Table 3.13-1 Environmental TLD Measurements Net Exposure in mR/Standard Quarter (91 days) 2020 Qtr Sta. 1st Quarter 2nd Quarter 3rd Quarter 4th Quarter Ave.

No. Description Exp. S.D. ~ S.D. Exp. S.D. ~ S.D. Exp.

TL-01 Brimmer's Lane 18.0 .:!:. 1.0 18.3 .:!:. 0.6 17.3 .:!:. 0.8 18.6 .:!:. 0.9 18.1 TL-02 Landing Road 13.0 + 0.8 14.0 .:!:. 0.5 13.2 .:!:. 0.6 14.3 .:!:. 0.7 13.6 TL-03 Glade Path 14.0 .:!:. 0.6 14.4 .:!:. 0.5 13.2 .:!:. 0.8 15.2 .:!:. 0.6 14.2 TL-04 Island Path 15.7 .:!:. 0.6 15.6 .:!:. 0.8 14.6 .:!:. 0.8 16.2 .:!:. 0.8 15.5 TL-05 Harbor Road 14.2 .:!:. 0.7 15.3 .:!:. 0.7 13.4 .:!:. 0.8 15.2 .:!:. 0.6 14.5 TL-06 Barge Landing 14.3 .:!:. 0.6 14.5 .:!:. 0.9 13.5 .:!:. 0.7 15.3 .:!:. 0.7 14.4 TL-07 Cross Road 12.8 + 0.7 13.2 .:!:. 0.6 11.7 .:!:. 0.5 13.8 .:!:. 0.7 12.9 TL-08 Farm Lane 15.1 .:!:. 0.7 15.7 + 0.8 14.3 + 0.7 15.8 .:!:. 0.9 15.2 TL-09 Farm Lane 16.4 .:!:. 0.8 16.4 .:!:. 0.5 15.4 .:!:. 0.7 17.2 .:!:. 0.8 16.4 TL-10 Site Boundary 14.8 + 0.8 16.7 .:!:. 0.5 14.9 .:!:. 0.9 18.6 + 1.2 16.3 TL-11 Site Boundary 17.2 .:!:. 0.8 19.3 .:!:. 1.0 16.9 .:!:. 1.0 19.9 .:!:. 0.9 18.3 TL-12 Site Boundary 18.4 .:!:. 0.9 19.0 .:!:. 0.9 18.2 .:!:. 0.8 20.0 .:!:. 0.8 18.9 TL-13 Inside Site Boundary 18.1 +/- 0.7 19.3 .:!:. 0.6 17.1 .:!:. 0.8 19.1 .:!:. 0.8 18.4 TL-14 Trailer Park 16.1 .:!:. 0.6 17.1 .:!:. 0.6 15.0 .:!:. 0.8 16.6 .:!:. 0.8 16.2 TL-15 Brimmer's Lane 18.5 .:!:. 0.9 18.6 .:!:. 0.7 18.8 .:!:. 0.9 19.9 .:!:. 1.0 19.0 TL-16 Brimmer's Lane 16.4 .:!:. 0.7 17.7 .:!:. 0.7 16.0 +/- 1.0 16.9 .:!:. 0.7 16.8 TL-17 South Road 14.6 .:!:. 0.6 15.4 .:!:. 1.2 15.0 .:!:. 0.9 15.4 .:!:. 0.8 15.1 TL-18 Mill Road 17.8 .:!:. 0.7 17.8 .:!:. 0.7 17.5 .:!:. 0.8 18.1 .:!:. 0.8 17.8 TL-19 Appledore Awnue 15.0 .:!:. 0.7 15.5 .:!:. 0.6 14.9 .:!:. 0.7 16.2 .:!:. 0.9 15.4 TL-20 Ashworth Awnue 16.9 .:!:. 0.9 17.3 .:!:. 0.6 15.4 .:!:. 0.7 17.5 .:!:. 0.6 16.8 TL-21 Route 1A 17.4 .:!:. 0.7 17.8 .:!:. 0.8 16.8 .:!:. 0.8 18.7 .:!:. 0.8 17.7 TL-22 Cable Awnue 16.0 .:!:. 0.8 16.0 .:!:. 0.7 15.3 .:!:. 0.7 16.8 .:!:. 0.7 16.0 TL-23 Ferry Road 15.5 .:!:. 0.8 15.8 .:!:. 0.8 14.9 .:!:. 0.6 16.4 .:!:. 0.6 15.7 TL-24 Ferry Lots Lane 17.5 .:!:. 0.8 17.4 .:!:. 0.7 17.5 .:!:. 0.8 17.9 .:!:. 0.6 17.6 TL-25 Elm Street 15.5 .:!:. 0.7 16.2 .:!:. 0.8 19.8 .:!:. 1.0 25.2 .:!:. 1.0 19.2 TL-26 Route 107A 15.0 .:!:. 0.6 14.8 .:!:. 0.5 14.4 .:!:. 0.9 16.7 .:!:. 0.6 15.2 TL-27 Highland Street 15.7 .:!:. 0.7 16.0 .:!:. 0.7 15.4 .:!:. 0.8 17.4 .:!:. 0.7 16.1 TL-28 Route 150 17.4 .:!:. 0.9 17.6 .:!:. 0.7 17.1 .:!:. 0.8 18.2 .:!:. 0.9 17.6 TL-29 Frying Pan Lane 14.7 .:!:. 0.6 16.1 .:!:. 0.7 15.5 .:!:. 0.7 16.7 + 0.7 15.8 TL-30 Route 27 16.4 .:!:. 0.7 17.3 .:!:. 0.6 16.7 + 0.8 18.3 .:!:. 1.2 17.2 TL-31 Alumni Driw 14.1 .:!:. 0.8 14.6 + 0.5 14.1 .:!:. 0.6 15.7 .:!:. 1.3 14.6 TL-32 SB Elementary School 18.4 .:!:. 0.7 18.2 .:!:. 0.6 17.2 .:!:. 0.7 15.0 .:!:. 0.6 17.2 TL-33 Dock Area 11.8 + 0.6 11.7 .:!:. 0.6 10.2 + 0.5 12.1 .:!:. 0.6 11.5 TL-34 Bow Street 19.5 .:!:. 0.8 21.2 .:!:. 0.7 20.0 .:!:. 0.9 21.6 .:!:. 0.8 20.6 TL-35 Lincoln Ack. School 17.5 .:!:. 0.7 18.4 .:!:. 0.8 17.6 .:!:. 0.8 19.2 .:!:. 0.8 18.2 TL-36 Route 97(Control) 14.7 .:!:. 0.5 15.5 .:!:. 0.6 14.0 + 0.7 15.3 .:!:. 0.7 14.9 TL-37 Plaistow, NH (Control) 17.4 + 0.7 18.3 .:!:. 0.7 17.6 .:!:. 0.9 18.7 .:!:. 0.7 18.0 TL-38 Hampstead, NH (Control) 17.9 .:!:. 0.8 19.0 .:!:. 0.6 17.6 .:!:. 0.9 19.4 .:!:. 0.7 18.5 Table 3.13-1 (Continued)

Environmental TLD Measurements Net Exposure in mR/Standard Quarter (91 days) 2020 Qtr.

Sta. 1st Quarter 2nd Quarter 3rd Quarter 4th Quarter Ave.

No. Description Exp. S.D. gm._ S.D. gm,. S.D. ~ S.D. Exp.

TL-39 Fremont, NH (Control) 20.2 .:!:. 0.8 21.9 .:!:. 0.6 20.3 .:!:. 0.9 21.2 .:!:. 0.8 20.9 TL-40 Newmarket, NH (Control) 16.2 .:!:. 0.8 17.5 .:!:. 0.7 17.0 .:!:. 0.8 17.7 .:!:. 0.8 17.1 TL-41 Portsmouth, NH (Control) 17.0 .:!:. 0.7 17.2 .:!:. 0.7 (1) 21.0 .:!:. 1.3 18.4 TL-42 Ipswich, MA (Control) 14.3 .:!:. 0.7 13.5 .:!:. 0.6 13.1 .:!:. 0.6 15.3 .:!:. 1.1 14.1 TL-44 SB Education Center 14.5 .:!:. 0.6 15.0 .:!:. 0.7 14.2 .:!:. 0.6 16.3 .:!:. 1.0 15.0 TL-45 Hampton Fire Station 16.2 .:!:. 0.9 16.6 .:!:. 0.6 14.9 .:!:. 0.8 16.9 .:!:. 0.7 16.2 TL-46 SB Police Station 16.5 .:!:. 0.8 17.6 .:!:. 0.8 16.0 .:!:. 0.9 17.3 .:!:. 0.9 16.9 TL-47 Route 84 16.1 .:!:. 0.8 16.8 .:!:. 0.6 16.2 .:!:. 0.7 17.2 .:!:. 0.6 16.6 Mean of Indicators 16.0 16.6 15.6 17.3 16.4 Mean of Controls 16.8 17.6 16.6 18.4 17.4 (1) TLD missing at time of collection.

Table 3.13-2 Pre-Operational Environmental TLD Measurements Net Exposure in mR/Standard Quarter (91 days)

Qtr Ave 1st Quarter 2nd Quarter 3rd Quarter 4th Quarter Over Yr Exp. Exp. Exp. Exp. Exp.

1982 Mean of Indicators 17.1 18.1 17.5 17.6 Mean of Controls 16.9 18.1 17.9 16.8 1983 Mean of Indicators 16.7 17.1 18.8 17.9 17.6 Mean of Controls 16.9 17.5 18.7 18.4 17.9 1984 Mean of Indicators 16.1 17.1 16.9 17.5 17.0 Mean of Controls 17.6 17.4 15.8 18.7 17.4 1985 Mean of Indicators 16.9 18.0 18.9 16.1 17.4 Mean of Controls 16.8 17.7 18.9 16.1 17.4 1986 Mean of Indicators 14.0 15.5 15.3 15.0 15.0 Mean of Controls 13.9 18.0 16.8 15.1 16.0 1987 Mean of Indicators 12.7 14.8 15.0 14.4 14.2 Mean of Controls 13.0 14.8 15.3 15.0 14.6 1988 Mean of Indicators 13.5 14.1 14.7 14.9 14.3 Mean of Controls 13.3 14.4 18.1 14.6 15.1 1989 Mean of Indicators 14.4 14.3 14.4 Mean of Controls 14.0 14.4 --- --- 14.2 All Pre-Operational Mean of Indicators 14.9 16.0 16.8 16.2 15.9 Mean of Controls 15.1 16.4 17.4 16.5 16.2 Table 3.13-3 Facility Related Dose using ANSl/HPS N13.37-2014 Methodology Quarterly Ave. Quarterly Facility Dose Annual 2020 Annual Facility Dose Annual 2020 Quarterly Monitoring Data, Baseline, Baseline, TLD M0 (mR/qtr)

Bo Fa = Mo - (Bo+MDDo) BA Data, MA FA= MA - (BA+MDDA) mR 1 2 3 4 1 2 3 4 mR mR TL-01 Brimmer's Lane 18.6 18.0 18.3 17.3 18.6 ND ND ND ND 74.5 72.2 ND TL-02 Landing Road 13.8 13.0 14.0 13.2 14.3 ND ND ND ND 55.1 54.6 ND TL-03 Glade Path 14.9 14.0 14.4 13.2 15.2 ND ND ND ND 59.5 56.8 ND TL-04 Island Path 15.9 15.7 15.6 14.6 16.2 ND ND ND ND 63.7 62.0 ND TL-05 Harbor Road 14.6 14.2 15.3 13.4 15.2 ND ND ND ND 58.1 58.1 ND TL-06 Barge Landing 14.6 14.3 14.5 13.5 15.3 ND ND ND ND 58.6 57.5 ND TL-07 Cross Road 12.5 12.8 13.2 11.7 13.8 ND ND ND ND 50.0 51.5 ND TL-08 Farm Lane 15.8 15.1 15.7 14.3 15.8 ND ND ND ND 63.1 60.9 ND TL-09 Farm Lane 16.3 16.4 16.4 15.4 17.2 ND ND ND ND 65.3 65.3 ND TL-10 Site Boundary 17.2 14.8 16.7 14.9 18.6 ND ND ND ND 68.7 65.0 ND TL-11 Site Boundary 17.5 17.2 19.3 16.9 19.9 ND ND ND ND 69.9 73.3 ND TL-12 Site Boundary 18.2 18.4 19.0 18.2 20.0 ND ND ND ND 72.6 75.6 ND TL-13 Inside Site Boundary 19.2 18.1 19.3 17.1 19.1 ND ND ND ND 77.0 73.5 ND TL-14 Trailer Park 15.9 16.1 17.1 15.0 16.6 ND ND ND ND 63.5 64.7 ND TL-15 Brimmer's Lane 18.8 18.5 18.6 18.8 19.9 ND ND ND ND 75.0 75.8 ND TL-16 Brimmer's Lane 16.2 16.4 17.7 16.0 16.9 ND ND ND ND 64.8 66.9 ND TL-17 South Road 16.3 14.6 15.4 15.0 15.4 ND ND ND ND 65.2 60.4 ND TL-18 Mill Road 15.5 17.8 17.8 17.5 18.1 ND ND ND ND 65.0 71.2 ND TL-19 Appledore Avenue 15.5 15.0 15.5 14.9 16.2 ND ND ND ND 62.1 61.6 ND TL-20 Ashworth Avenue 17.5 16.9 17.3 15.4 17.5 ND ND ND ND 70.2 67.0 ND TL-21 Route 1A 16.6 17.4 17.8 16.8 18.7 ND ND ND ND 66.3 70.7 ND TL-22 Cable Avenue 16.3 16.0 16.0 15.3 16.8 ND ND ND ND 65.4 64.1 ND TL-23 Ferry Road 15.7 15.5 15.8 14.9 16.4 ND ND ND ND 62.7 62.7 ND Table 3.13-3 (Continued)

Facility Related Dose using ANSl/HPS N13.37-2014 Methodology Annual Facility Quarterly Ave. Quarterly Facility Dose Annual 2020 Dose Annual 2020 Quarterly Monitoring Data, M0 Baseline Baseline TLD FA= MA -

(mR/qtr)

Bo Fo = Mo - (Bo+MDDo) BA Data, MA (BA+MDDA) mR 1 2 3 4 1 2 3 4 mR mR TL-24 Ferry Lots Lane 16.0 17.5 17.4 17.5 17.9 ND ND ND ND 63.9 70.2 ND TL-25 Elm Street 15.6 15.5 16.2 19.8 25.2 ND ND ND 9.65 62.3 76.8 14.61 TL-26 Route 107A 15.4 15.0 14.8 14.4 16.7 ND ND ND ND 61.8 61.0 ND TL-27 Highland Street 16.1 15.7 16.0 15.4 17.4 ND ND ND ND 64.3 64.5 ND TL-28 Route 150 16.2 17.4 17.6 17.1 18.2 ND ND ND ND 64.9 70.3 ND TL-29 Frying Pan Lane 15.4 14.7 16.1 15.5 16.7 ND ND ND ND 61.6 62.9 ND TL-30 Route 27 15.7 16.4 17.3 16.7 18.3 ND ND ND ND 62.9 68.7 ND TL-31 Alumni Drive 14.3 14.1 14.6 14.1 15.7 ND ND ND ND 57.0 58.5 ND TL-32 SB Elementary School 17.8 18.4 18.2 17.2 15.0 ND ND ND ND 71.2 68.7 ND TL-33 Dock Area 21.4 11.8 11.7 10.2 12.1 ND ND ND ND 84.4 45.8 ND TL-34 Bow Street 19.5 19.5 21.2 20.0 21.6 ND ND ND ND 78.2 82.3 ND TL-35 Lincoln Ack. School 18.2 17.5 18.4 17.6 19.2 ND ND ND ND 72.6 72.6 ND TL-36 Route 97(Control) 15.4 14.7 15.5 14.0 15.3 ND ND ND ND 61.9 59.5 ND TL-37 Plaistow, NH (Control) 18.0 17.4 18.3 17.6 18.7 ND ND ND ND 72.0 72.0 ND TL-38 Hampstead, NH (Control) 19.8 17.9 19.0 17.6 19.4 ND ND ND ND 79.3 73.9 ND TL-39 Fremont, NH (Control) 21.3 20.2 21.9 20.3 21.2 ND ND ND ND 85.2 83.6 ND TL-40 Newmarket, NH (Control) 16.7 16.2 17.5 17.0 17.7 ND ND ND ND 66.9 68.3 ND TL-41 Portsmouth, NH (Control) 16.9 17.0 17.2 (2) 21.0 ND ND ND ND 67.6 55.2 ND TL-42 Ipswich, MA (Control) 14.3 14.3 13.5 13.1 15.3 ND ND ND ND 57.2 56.2 ND TL-44 SB Education Center 14.8 14.5 15.0 14.2 16.3 ND ND ND ND 59.0 60.0 ND MDDo = 4.55 = minimum differential exposure, quarterly, 3 times 90th percentile So determined from analysis in mR.

MDDA = 8.97 = minimum differential exposure, annual, 3 times 90th percentile SA determined from analysis in mR.

Bo = Quarterly baseline exposure (mR).

Mo = location's 91 day standard quarterly exposure (mR).

Lo= Quarterly Investigative Level exposure (mR).

BA = Quarterly baseline background average exposure (mR).

MA= Annual monitoring data, determined by summing the quarterly data over all four quarters (mR).

LA = Annual Investigative Level exposure (mR).

ND = Facility contribution to exposure "Not Detected" (1) An annual dose of 14.6 mR was calculated for location TL-25 using the ANSl/HPS N13.37-2014 methodology and the baseline values calculated using data from 2004 to 2014. However, this dose was determined not to be facility related due to the distance of this TLD location with respect to the plant (7.6 km) and the lack of any observed dose for TLD locations closer to the plant. The observed dose is likely a result of a change in the environment at the TLD location. Figure 3.10.1 shows ? step increase in the quarterly TLD values for this location starting in 2020. For this reason, the location will continue to be monitored and the quarterly and annual baseline values for this location will be adjusted, as necessary.

(2) TLD missing at time of collection FIGURE 3.6 ENVIRONMENTAL RADIATION MEASUREMENTS (USING TLDs) SEABROOK STATION 40 30 30 Q) t:

CIJ

J 0.._ 20 20 Q) a.

n::

E 10 10 0

Qtr. 1 Qtr. 2 Qtr. 3 Qtr. 4 2020

~ TL-01 Brimmer's Lane

--e- TL-02 Landing Road

--er- TL-03 Glade Path

- + - TL-05 Harbor Road FIGURE 3.6.1 ENVIRONMENTAL RADIATION MEASUREMENTS (USING TLDs)

SEABROOK STATION

~ ~

.... 20 QI

~ /I I - r.I I\ - TL 1i 7i Lt/ _ i;;;i i;;;i + 20 t:

I'll

l 0

QI c.

0::

E 10 ~ + 10 0 0 1986 1988 1990 1992 1994 1996 1998 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020

--B--TL-01 Brimmer's Lane

---e- TL-02 Land ing Road

---i!r- TL-03 Glade Path

~ T L-04 Island Path

---*- TL-05 Harbor Road FIGURE 3.7 ENVIRONMENTAL RADIATION MEASUREMENTS (USING TLDs)

SEABROOK STATION 40.0 30.0 Q) t'.

ro

J 020.0 Q) 0..

0:::

E 10.0 0.0 Qtr-1 Qtr-2 Qtr-3 Qtr-4 2020

-s-- TL-06 Barge Landing

--e- TL-07 Cross Road

-tr- TL-08 Farm Lane

---<>- TL-09 Farm Lane

~ TL-1 O Site Boundary FIGURE 3. 7.1 ENVIRONMENTAL RADIATION MEASUREMENTS (USING TLDs)

SEABROOK STATION 30 30 20 I /l )f:~flf ! I 20 Q) t::

'}(

'-./ ¥ ro

J a.....

Q) c._

0::

E 10 -I ~

~

\I 10 0 0 1986 1988 1990 1992 1994 1996 1998 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020

-e- TL-06 Barge Landing

- G - TL-07 Cross Road

-tr- TL-08 Farm Lane

- TL-09 Farm Lane

~ TL-10 Site Boundary FIGURE 3.8 ENVIRONMENTAL RADIATION MEASUREMENTS (USING TLDs)

SEABROOK STATION 40 30 30

~rn

J a..... 20 20 Q) 0..

0::

E 10 10 0

Qtr. 1 Qtr. 2 Qtr. 3 Qtr. 4 2020

---e-- TL-11 Site Boundary

--e- TL-12 Site Bounda ry

-ts- TL-13 Inside Site Boundary

~ TL-1 4 Trailer Park

~ TL-15 Brimme r's Lane FIGURE 3.8.1 ENVIRONMENTAL RADIATION MEASUREMENTS (USING TLDs)

SEABROOK STATION 30 ...-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~-.

30 20 ~ 'AA

A ~~ 4ft:4 jA__d JS M .t::'t... ~L\.Q .,.. .t. ,,, ~fid~ .a /\ M./!Unl\' lii,.... .JIA ~ ~ w~ ~ - _ lil ~ lit 20 Q) t::

(1)

J a.....

Q) c.

0::

E 10 ~ ~ 10 0 0 1986 1988 1990 1992 1994 1996 1998 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020

--B- TL-11 Site Boundary

---G- TL-12 Site Boundary

-fr- TL-13 Inside Site Boundary

~ TL-14 Trailer Park

- TL-15 Brimmer's Lane FIGURE 3.9 ENVIRONMENTAL RADIATION MEASUREMENTS (USING TLDs) SEABROOK STATION 40 30 30

~co

J

<2 20 20 Q) 0..

0:::

E 10 10 0

Qtr. 1 Qtr. 2 Qtr. 3 Qtr. 4 2020

-a-- TL-16 Brimmer's Lane

--e--- TL-17 South Road

-tr- TL-18 Mill Road

- TL-19 Appledore Avenue

- + - TL-20 Ashworth Avenue FIGURE 3.9.1 ENVIRONMENTAL RADIATION MEASUREMENTS (USING TLDs) SEABROOK STATION 30 .---~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~--.-

30 i '!\ ~ ¥ II /\ff: ~ 20 2.....

ro

i 20

"' 'JI: ¥ a.....

Q) a.

0::

E - -

z:s. x ~ !::. = I 7'

10 ]Cl i [ 10 0 0 1986 1988 1990 1992 1994 1996 1998 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020

~ TL-16 Brimmer's Lane

--e- TL-17 South Road

---6--- TL-1 8 Mi II Road

---<>-- TL-19 App ledore Avenue

- TL-2 0 Ashworth Avenue FIGURE 3.10 ENVIRONMENTAL RADIATION MEASUREMENTS (USING TLDs)

SEABROOK STATION 30 30

~(I)

I a..... 20 20 Q) 0..

0:::

E 10 10 Qtr. 1 Qtr. 2 Qtr. 3 Qtr. 4 2020

-&- TL-21 Route 1A

-B- TL-22 Cable Avenue

--tr- TL-23 Ferry Road

~ TL-24 Ferry Lots Lane

- * - TL-25 Elm Street FIGURE 3.10.1 ENVIRONMENTAL RADIATION MEASUREMENTS (USING TLDs)

SEABROOK STATION 30 30 20 -l lil!iJ ,.,, H 20

~<1l 0

Qi Q.

a::

E x ~

~

1J t 10

~:.98~6~--:;:::-.-:-;:;::;:-'~:::---r---=--:::::-:--~-=-=~~--.-~~~~--r--~~~~~~~.-~~~~--.---~~~~~--.~.-~_J 2012 2014 2016 2018 2020 0

1988 1990 1992 1994 1996 1998 2000 2002 2004 2006 2008 2010

-e- TL-21Route1A

---e--- TL-22 Cable Avenue

e.- TL-23 Ferry Road

~ TL-24 Ferry Lots Lane

---*- TL-25 Elm Street FIGURE 3.11 ENVIRONMENTAL RADIATION MEASUREMENTS (USING TLDs) SEABROOK STATION 40 30 30 Q) t ro 020 20 Q) 0..

0:::

E 10 10 0 0 Qtr. 1 Qtr. 2 Qtr. 3 Qtr. 4 2020

-Et- TL-26 Route 107A

--e- TL-27 Highland Street

---tr- TL-28 Route 150

~ TL-29 Frying Pan Lane

~ TL-30 Route 27 FIGURE 3.11 .1 ENVIRONMENTAL RADIATION MEASUREMENTS (USING TLDs)

SEABROOK STATION 30~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

30 20 -l ~ 20

~

a"':::s iiia.

!l:'.

E

I( i!l 10 J I l 10 0 +---.~-.-~~~~~~~~~~~~~~~~--.~-.-~~~~~~~~~~;---~~~~~--.~-.-~~~~~~~~~~~~~~~~--.;---_.,... 0 1986 1988 1990 1992 1994 1996 1998 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020

-B- TL-26 Route 107A

-G- TL-27 Highland Street

--rr- TL-28 Route 150

-<>- TL-29 Frying Pan Lane

- - - rL-30 Route 27 FIGURE 3.12 ENVIRONMENTAL RADIATION MEASUREMENTS (USING TLDs)

SEABROOK STATION 40 30

~Cll

J

'2 Q) 20 c..

0:::

E 10 0

Qtr. 1 Qtr. 2 Qtr. 3 Qtr. 4 2020

-e- TL-31 Alumni Drive

--e--- TL-32 SB Elementarty School

--tr- TL-33 Dock Area

~ TL-34 Bow Street

- * - TL-35 Lincoln Ackerman School FIGURE 3.12.1 ENVIRONMENTAL RADIATION MEASUREMENTS (USING TLDs)

SEABROOK STATION 30 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

30 20 i A

"'fx "A !iM d(A~.1M11/~W ~~ vR UAJM!J~~a~~~~ 20

(])

t co

=i a,_

(])

c..

c::

E 10 -j [!] Ll.

A+ 10 0 0 1986 1988 1990 1992 1994 1996 1998 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020

- B - TL-31 Alumni Drive

--e-- TL-32 SB Elementary School

---fr- TL-33 Dock Area

--e--- TL-34 Bow Street

~ TL-35 Lincoln Ackerman School FIGURE 3.13 ENVIRONMENTAL RADIATION MEASUREMENTS (USING TLDs) SEABROOK STATION 40 30 30

~ro

J a 20 20 Q;

0..

er:::

E 10 10 0

Qtr. 1 Qtr. 2 Qtr. 3 Qtr. 4 2020

-ti- TL-36 Route 97 (Control)

~ TL-37 Plaistow , NH (Control)

~ TL-38 Hampstead NH (Control)

-+- TL-39 Fremont , NH (Control)

- - TL-40 Newmarket , NH (Control)

FIGURE 3.13 .1 ENVIRONMENTAL RADIATION MEASUREMENTS (USING TLDs)

SEABROOK STATION 30 30 20 -l ~\ II ~ .AAn A ~A ~ ~ TIA & ~ ~"~" 4l.A. 1p, ~JA.rr v:\rt'.1 M..~tt *~ ~rl t~ \~)op v ~~. ~ 20 Q) t ro

s a......

Q) c..

0:::

E

~ ~

~

10 10 0 0 1986 1988 1990 1992 1994 1996 1998 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020

-e- TL-36 Route 97 (Control)

~ TL-37 Plaistow, NH (Control)

--6---- TL-38 Hampstead NH (Control)

-+-- TL-39 Fremont , NH (Control)

- - - rL-40 Newmarket , NH (Control)

FIGURE 3.14 ENVIRONMENTAL RADIATION MEASUREMENTS (USING TLDs)

SEABROOK STATION 40 30 30

~

ro

l D

0,_ 20 20 Q) c..

c:::

E 10 10 0

Qtr. 1 Qtr. 2 Qtr. 3 Qtr. 4 2020

---e- TL-41 Portsmouth, NH (Control)

--e- TL-42 Ipswich, MA (Control)

~ TL-44 SB Education Center

~ TL-45 Hampton Fire Station

TL-46 SB Beach Police Station

~ TL-47 Hampton Falls, Route 84 FIGURE 3.14.1 ENVIRONMENTAL RADIATION MEASUREMENTS (USING TLDs)

SEABROOK STATION 30 30 20 ~ I II n r 20 Q)

-e

<13

J a.....

Q) c..

0:::

E 10 -l - r 10 0 0 1986 1988 1990 1992 1994 1996 1998 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020

-B- TL-41 Portsmouth, NH (Control)

-+- TL-42 Ipswich, MA (Control)

--6-- TL-43 Rocks Road Landing

--+- TL-44 SB Education Center

- - TL-45 Hampton Fire Station

- TL-46 SB Beach Police Station

-+- TL-47 Hampton Falls, Route 84 4.0 Dry Fuel Storage REMP & Data Summary The Dry Fuel Storage (DFS) radiological environmental monitoring program required by ODCM Control C.9.4.1 provides representative measurements of direct (including scattered) radiation exposure at those locations that have the highest potential for dose to members of the public resulting from dry fuel storage operations. The design of the storage facility is such that there are no liquid or gaseous effluents released to the environment from DFS and, therefore, no associated exposure pathways for liquids and gases requiring the collection and analysis of such sample media. As a result, only direct (including scattered) radiation from the DFS modules need to be monitored for integrated exposures in areas where doses to members of the public need to be limited.

At locations near the DFS where members of the public might be present (off-site areas near the site boundary and on-site special use locations, i.e., the Science and Nature Center, the new Fitness Center located in the High Rise office building east of the DFS facility and the Firing Range located on the west site boundary}, TLDs were placed at least 1 year (4 quarterly measurements) prior to used fuel being placed into storage. The DFS received its first load of fuel for storage on July 28, 2008. A total of 6 fuel canisters were placed in the NUHOMS© Horizontal Storage Modules (HSM) on the DFS pad during 2008 with the last one being loaded on September 4, 2008. A second fuel transfer campaign was conducted during August and September, 2013, with an additional 8 fuel canisters placed into storage, and a third fuel transfer campaign during August- October 2017 with an additional 8 fuel canisters bringing the total to 22 canisters in storage.

The DFS radiological environmental monitoring stations are listed in Table 4.0-1. At the end of 2013, TLD location SB-35, which was located inside the old Fitness Center, and location TL-67 (first quarter of 2014), which was located outside the old Fitness Center south of the DFS, were removed from the program due to the relocation of the fitness center to the High Rise Office Building. TLD locations SB-32 and SB-33 now provide monitoring for the new Fitness Center location. The measurement locations with respect to the Seabrook site area are shown on Figure 4.0.1.

4.1 Direct Radiation from DFS As with the plant operations TLD program described in Section 3.13, the DFS TLD exposure rates were normalized to a standard 91-day quarter. A summary of the 2020 data for the DFS REMP is shown in Table 4.1-1. Figures 4.1, 4.2 and 4.3 show the quarterly 2020 TLD trend lines for the control and indicator monitoring locations. Figures 4.4, 4.5 and 4.6 provide a comparison of long term trend lines (12 years) for the same control locations, site boundary and special use sites.

Overall, the direct radiation program showed no statistically significant indication of increased direct radiation above the variable background measured exposure rate in unrestricted areas. The 2020 annual mean of all indicator locations for the DFS was 17.2 mR/91-day quarter while the mean of all control locations was 17.4 mR/91-day quarter. There was no notable difference detected in the annual exposure rates in areas were members of the public could occupy (site boundary and inside special use locations) and the control locations. Starting in the 4th quarter of 2013, location TL-67 indicated a notable measurement increase in exposure rate following the expansion of fuel storage in the DFS facility in the third quarter of 2013. However, by late November, 2013, the fitness center operations had been transferred from its original location south of the DFS to the High Rise Office Building east of the DFS, thereby ending use of the original fitness center facility and its parking lot by members of the public.

Starting in 2015, an additional analytical method was implemented to evaluate the TLD measurements.

Using the method described in ANSl/HPS N13.37-2014, quarterly and annual baseline dose for each DFS TLD location was determined using appropriate statistical analytical methods considering data from 2004 through 2014. Quarterly and annual dose for 2020 was compared to baseline values to determine if an Investigation Level had been exceeded for evaluation of potential dose to a member of the public. An Investigation Level is considered to be exceeded under the following conditions:

Quarterly: If M0 >(Bo+ MDD 0 ), then F0 = M0 - Bo Where:

M 0 is the normalized quarterly field measurement result B0 is the quarterly baseline background dose MDD 0 is the quarterly minimum differential dose and F0 is the quarterly facility related dose or: Annually: If MA > (BA + MDDA), then FA = MA - BA Where:

MA is the sum of the four normalized quarterly measurement values BA is the annual baseline background dose MDDA is the annual minimum differential dose FA is the annual facility related dose Table 4.1-2 summarizes the evaluation of the TLD measurements using the methodology described in ANSl/HPS N13.37-2014. As noted in Table 4.1-2, TLD location SB-33 (High-Rise Building 151 floor, Fitness Center) was found to have a calculated annual facility related dose of 12.6 mR when comparing the measured TLD value against the annual baseline values. However, as this is an onsite fitness center under Station control, an annual occupancy factor for this location of 0.0416 (1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months per day x 7 days a week x 52 weeks per year I 8760 hours0.101 days 2.433 hours 0.0145 weeks 0.00333 months ) can be applied. This results in an annual dose of 0.5 mR Any sample collection and analysis deviations from the ODCM required program, or reportable concentrations that may have occurred during the year are described in Section 5.

Figure 4.0.1 Monitoring Locations Dry Fuel Storage TLD Environmental Table 4.0-1 Dry Fuel Storage (DFS) TLD Monitoring Locations TLD Sample Location Distance From Direction From Site Designation Code DFS Pad DFS Pad Description( 3)

(km)

TL-44 On-site, outside Science & Nature Center (1)( 2) 0.21 ESE SB-36 On-site, inside Science & Nature Center 0.24 SE SB-32 High-Rise Building, 3rd Floor( 1) 0.23 E SB-33 High-Rise Building, 1st Floor (new Fitness Center)( 1) 0.23 E TL-68 Nearby site boundary (firing range) to DFS 0.45 w TL-69 Nearby site boundary (Rocks Rd) to DFS 0.47 w TL-10 Site Boundary Fence (2) 0.77 s TL-11 Site Boundary Fence (2 ) 0.52 SSW TL-12 Site Boundary fence (2) 0.53 WSW TL-13 Inside Site Boundary (2) 0.61 WNW TL-14 Trailer Park, Seabrook (2) 0.94 NW TL-36 Rt 97, Georgetown (Control) (2l 22 SSW TL-37 Plaistow, NH (Control) (2l 21 WSW TL-38 Hampstead, NH (Control) (2 l 27 w TL-39 Fremont, NH (Control) (2) 27 WNW TL-40 Newmarket, NH (Control) (2 l 22 NNW TL-41 Portsmouth, NH (Control) (1J( 2 l 22 NNE TL-42 Ipswich, MA (Control) (1J( 2 l 22 SSE (1) This location is not part of the required DFS radiological monitoring program as defined in Table A.9.4-1 of the Seabrook ODCM.

(2) Shared environmental monitoring locations for both Seabrook Station REMP and DFS monitoring.

(3) TL-67 and SB-35 locations were removed in 2014 due to relocation of the Fitness Center to the High Rise office building.

Table4.1-1 DFS Environmental TLD Measurements Net Exposures in mR/Standard Quarter (91 days) 2020 Sta. 1st Quarter 2nd Quarter 3rd Quarter 4th Quarter Qtr Ave No. Description Exp. S.D. ~ S.D. Exp. S.D. ~ S.D. Exp.

TL-44 Outside Science & Nature C.(1) 14.5 +/- 0.6 15.0 +/- 0.7 14.2 +/- 0.6 16.3 +/- 1.0 15.0 SB-36 Inside Science & Nature C. 16.9 +/- 0.8 16.9 +/- 0.7 15.4 +/- 0.7 18.0 +/- 0.5 16.8 SB-32 High-Rise 3rd Floor ( 1) 14.4 +/- 0.7 14.9 +/- 0.7 14.7 +/- 0.8 15.3 +/- 0.6 14.8 SB-33 High-Rise 1st Fl.(Fitness Cntr)(1) 20.1 +/- 0.9 20.9 +/- 0.7 19.2 +/- 0.9 21.5 +/- 1.0 20.4 TL-68 Nearby Site Boundary to DFS 18.5 +/- 0.9 18.7 +/- 0.8 18.3 +/- 0.9 19.8 +/- 0.8 18.8 TL-69 Nearby Site Boundary to DFS 15.2 +/- 0.9 14.9 +/- 0.8 14.4 +/- 0.9 16.1 +/- 0.8 15.2 TL-10 Site Boundary Fence (2) 14.8 +/- 0.8 16.7 +/- 0.5 14.9 +/- 0.9 18.6 +/- 1.2 16.3 TL-11 Site Boundary Fence (2) 17.2 +/- 0.8 19.3 +/- 1.0 16.9 +/- 1.0 19.9 +/- 0.9 18.3 TL-12 Site Boundary Fence (2) 18.4 +/- 0.9 19.0 +/- 0.9 18.2 +/- 0.8 20.0 +/- 0.8 18.9 TL-13 Inside Site Boundary (2) 18.1 +/- 0.7 19.3 +/- 0.6 17.1 +/- 0.8 19.1 +/- 0.8 18.4 TL-14 Trailer Park Seabrook (2) 16.1 +/- 0.6 17.1 +/- 0.6 15.0 +/- 0.8 16.6 +/- 0.8 16.2 TL-36 Rt 97, Georgetown ( control)(2) 14.7 +/- 0.5 15.5 +/- 0.6 14.0 +/- 0.7 15.3 +/- 0.7 14.9 TL-37 Aaistow, NH (Control)(2) 17.4 +/- 0.7 18.3 +/- 0.7 17.6 +/- 0.9 18.7 +/- 0.7 18.0 TL-38 Hampstead, NH (Control)(2) 17.9 +/- 0.8 19.0 +/- 0.6 17.6 +/- 0.9 19.4 +/- 0.7 18.5 TL-39 Fremont, NH (Control)(2) 20.2 +/- 0.8 21.9 +/- 0.6 20.3 +/- 0.9 21.2 +/- 0.8 20.9 TL-40 New market, NH (Control)(2) 16.2 +/- 0.8 17.5 +/- 0.7 17.0 +/- 0.8 17.7 +/- 0.8 17.1 TL-41 Portsmouth, NH (Control)(1)(2) 17.0 +/- 0.7 17.2 +/- 0.7 (3) 21.0 +/- 1.3 18.4 TL-42 lpsw ich, MA (Control)(1)(2) 14.3 +/- 0.7 13.5 +/- 0.6 13.1 +/- 0.6 15.3 +/- 1.1 14.1 Mean of Indicators 16.7 17.5 16.2 18.3 17.2 Mean of Controls 16.8 17.6 16.6 18.4 17.4 (1) This location is not part of the DFS required program defined by the ODCM.

(2) Shared environmental monitoring locations for both plant RBvlP and DFS monitoring.

(3) TLD missing at time of collection.

Table 4.1-2 DFS Facility Related Dose using ANSl/HPS N13.37-2014 Methodology Annual Quarterly 2020 Facility 2020 Quarterly Monitoring Annual Dose Ave. Annual Data, MQ (mR/qtr) TLD Baseline, Quarterly Facility Dose Baseline, FA= MA -

BQ FQ = MQ - (BQ+MDDQ) BA Data, MA (BA+MDDA) mR I 1 2 3 4 I 1 2 3 4 I mR mR On-site, outside Science &

TL-44 Nature Center 14.8 I 14.5 15.0 14.2 16.3 I ND ND ND ND I 59.0 60.0 ND On-site, inside Science &

SB-36 Nature Center 16.2 I 16.9 16.9 15.4 18.0 I ND ND ND ND I 64.7 67.3 ND High-Rise Building, 3rd SB-32 floor 14.0 I 14.4 14.9 14.7 15.3 I ND ND ND ND I 55.7 59.4 ND High-Rise Building 1st SB-33 floor, Fitness Center 17.5 I 20.1 20.9 19.2 21.5 I ND ND ND ND I 69.2 81.8 12.61 Nearby site boundary TL-68 (firing Range) 17.7 I 18.5 18.7 18.3 19.8 I ND ND ND ND I 70.8 75.2 ND Nearby site boundary TL-69 (Rocks Rd) 14.6 15.2 14.9 14.4 16.1 ND ND ND ND 58.2 60.5 ND TL-10 Site Boundary 17.2 14.8 16.7 14.9 18.6 ND ND ND ND 68.7 65.0 ND TL-11 Site Boundary 17.5 17.2 19.3 16.9 19.9 ND ND ND ND 69.9 73.3 ND TL-12 Site Boundary 18.2 18.4 19.0 18.2 20.0 ND ND ND ND 72.6 75.6 ND TL-13 Inside Site Boundary 19.2 18.1 19.3 17.1 19.1 ND ND ND ND 77.0 73.5 ND TL-14 Trailer Park 15.9 16.1 17.1 15.0 16.6 ND ND ND ND 63.5 64.7 ND TL-36 Route 97(Control) 15.4 14.7 15.5 14.0 15.3 ND ND ND ND 61.9 59.5 ND TL-37 Plaistow, NH (Control) 18.0 17.4 18.3 17.6 18.7 ND ND ND ND 72.0 72.0 ND TL-38 Hampstead, NH (Control) 19.8 17.9 19.0 17.6 19.4 ND ND ND ND 79.3 73.9 ND TL-39 Fremont, NH (Control) 21.3 20.2 21.9 20.3 21.2 ND ND ND ND 85.2 83.6 ND TL-40 Newmarket, NH (Control) 16.7 16.2 17.5 17.0 17.7 ND ND ND ND 66.9 68.3 ND TL-41 Portsmouth, NH (Control) 16.9 17.0 17.2 21.0 ND ND ND ND 67.6 55.2 ND TL-42 Ipswich, MA (Control) 14.3 14.3 13.5 13.1 15.3 ND ND ND ND 57.2 56.2 ND

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Table 4.1-2 (cont'd)

DFS Facility Related Dose using ANSl/HPS N13.37-2014 Methodology MDD 0 = 4.48 = minimum differential exposure, quarterly, 3 times 90th percentile S 0 determined from analysis in mR.

MDDA = 10.17 = minimum differential exposure, annual, 3 times 90th percentile SA determined from analysis in mR.

Bo = Quarterly baseline exposure (mR).

M0 = location's 91 day standard quarterly exposure (mR).

L0 =Quarterly Investigative Level exposure (mR).

BA = Quarterly baseline background average exposure (mR).

MA= Annual monitoring data, determined by summing the quarterly data over all four quarters (mR).

LA= Annual Investigative Level exposure (mR).

ND = Facility contribution to exposure "Not Detected" 1 Note that this location is a fitness center and is not occupied full time. Applying an annual occupancy factor for this location of 0.0416 (1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months per day x 7 days a week x 52 weeks per year I 8760 hours0.101 days 2.433 hours 0.0145 weeks 0.00333 months ), results in an annual dose of 0.5 mR.

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FIGURE 4.1 DFS CONTROL RADIATION MEASUREMENTS (USING TLDs)

SEABROOK STATION 40 30 30 Q;

t:'.

ro

J a 20 20 Q;

c..

0::

E 10 10 0

Qtr. 1 Qtr. 2 Qtr. 3 Qtr. 4 2020

- e - TL-41 Portsmouth, NH (Control)

-e-- TL-42 Ipswich , MA (Control)

---er- TL-36 Route 97 (Control)

--+-- TL-37 Plaistow, NH (Control)

- TL-38 Hampstead NH (Control)

-+- TL-39 Fremont, NH (Control)

- - Control Average 7 stations

--+-- TL-40 Newmarket, NH (Control)

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FIGURE 4.2 DFS ENVIRONMENTAL RADIATION MEASUREMENTS (USING TLDs)

SEABROOK STATION 40.0 30.0 CD t

<1l

l 20.0 CD c..

0:::

E 10.0 0.0 Qtr. 1 Qtr. 2 Qtr. 3 Qtr. 4 2020

---a-- TL-10 Site Boundary Fence

fr-- TL-12 Site Boundary Fence

- + - TL-13 Inside Site Boundary

~ TL-14 Trailer Park

- ~ - Control Average 7 stations

--e-- TL-11 Site Boundary Fence

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FIGURE 4.3 DFS ENVIRONMENTAL RADIATION MEASUREMENTS (USING TLDs)

SEABROOK STATION 40 30 30 t

Qi ro

i 020 QJ c.

)(

-*-*-*-*- *-* -._ - *-. 20 0:::

E 10 10 0

Qtr. 1 Qtr. 2 Qtr. 3 Qtr. 4 2020

--a-- TL-44 Outside Science & Nature Center

~ SB-36 Inside Science & Nature Center

+E-- TL-68 Near Site Boundary to DFS

--+-- TL-69 Near Site Boundary to DFS

---e--- Control Average 7 stations

- - - SB-32 High-Rise 3rd Fl.

- * ** - SB-33 High-Rise 1st Fl. (new Fitness Cntr.)

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FIGURE 4.4 DFS CONTROL RADIATION MEASUREMENTS (USING TLDs)

SEABROOK STATION First DFS loading, July 20 20 Q) t::

(1)

J a

Q; 0..

0:::

E 10 10 2nd DFS loading, Completed Sept. 3rd DFS loading, 2013 Completed Oct.

2017 0 0 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 201 7 2018 2019 2020 years

- e - - TL-41 Portsmouth, NH (Control)

~ TL-42 Ipswich, MA (Control)

- t s - TL-36 Route 97 (Control)

~ TL-37 Plaistow, NH (Control)

~ TL-38 Hampstead NH (Control)

--+- TL-39 Fremont, NH (Control)

---e--- Control Average 7 stations

--+-- TL-40 Newmarket, NH (Control)

-1 05-

FIGURE 4.5 DFS RADIATION MEASUREMENTS TRENDS (USING TLDs)

SEABROOK STATION First DFS loading ,

July 2008 20 20 (i) t co

J a.....

<l>

a.

c:::

E 10 10 2nd DFS loading ,

Completed

/

3rd DFS loading ,

Completed Oct.

2017 0 0 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 years

-e-- TL-10 Site Boundary Fence

~ TL-11 Site Boundary Fence

-er- TL-12 Site Boundary Fence

---+-- TL-13 Inside Site Boundary

~ TL-14 Trailer Park

--+-- TL-39 Fremont, NH (Control)

---e--- Control Average 7 stations

--+-- TL-40 Newmarket, NH (Control)

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FIGURE 4.6 DFS RADIATION MEASUREMENTS TRENDS (USING TLDs)

SEABROOK STATION 30 First DFS loading ,

July 2008 20 20 Q) t::

ro

~

a.....

Q) 0..

D:'.

E 10 10 2nd DFS 3rd DFS loadi g ,

loading, Compreted Sept. Completed 2013 Oct. 2017 0 0 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 years

--a-- TL-44 Outside Science & Nature Center - e - - SB-36 Inside Science & Nature Center

6-- TL-67 Outside Old Fitness Center - SB-35 Inside Old Fitness Center

- - TL-68 Near Site Boundary to DFS - TL-69 Near Site Boundary to DFS

---e--- Control Average 7 stations - .,. - TL-40 Newmarket, NH (Control)

--+-- TL-39 Fremont, NH (Control) - SB-32 High-Rise 3rd Fl.

- - - - SB-33 High-Rise 1st Fl. (new Fitness Cntr.)

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5.0 Program Deviations and Reporting 5.1 Sampling Program Deviations Table A.9.1-1 of the Offsite Dose Calculation Manual (ODCM) allows for deviations in the REMP sampling schedule "if specimens are unobtainable due to circumstances such as hazardous conditions, seasonal unavailability and malfunction of automatic sampling equipment." All deviations from the sampling schedule shall be documented each year in the Radiological Environmental Operating Report. The deviations for 2020 are as follows:

On March 15, 2020, the REMP air sampling station in the plateyard (AP/CF-04) lost AC power.

The out of service time did not impact the ability to collect sufficient sample volume over the collection cycle for this analysis. AR 02348540 was written to document and track this issue.

On May 22, 2020, the REMP air sampling station in the plateyard (AP/CF-04) lost AC power. The out of service time did not impact the ability to collect sufficient sample volume over the collection cycle for this analysis. AR 02357460 was written to document and track this issue.

On June 5, 2020, the REMP air samplers in Exeter/Hampton (AP/CF-08), the Rock Pile (AP/CF-03), and Barge Landing (AP/CF-01) lost AC power. The out of service time did not impact the ability to collect sufficient sample volume over the collection cycle for this analysis. AR 02358872 was written to document and track this issue.

On July 7, 2020, the second quarter TLD SB-15 (Warehouse #2) was found to be missing. AR 02362045 was written to document and track this issue.

On July 31, 2020, the REMP air samplers in Exeter/Hampton (AP/CF-08), the Rock Pile (AP/CF-03), and Barge Landing (AP/CF-01) lost AC power. The out of service time did not impact the ability to collect sufficient sample volume over the collection cycle for this analysis. AR 02364274 was written to document and track this issue.

On August 14, 2020, the REMP air samplers in Exeter/Hampton (AP/CF-08), and Barge Landing (AP/CF-01) lost AC power. The out of service time did not impact the ability to collect sufficient sample volume over the collection cycle for this analysis. AR 02365449 was written to document and track this issue.

On September 9, 2020, the REMP air samplers in Exeter/Hampton (AP/CF-08), the Rock Pile (AP/CF-03), and Barge Landing (AP/CF-01) lost AC power. The out of service time did not impact the ability to collect sufficient sample volume over the collection cycle for this analysis. AR 02367876 was written to document and track this issue.

On September 13, 2020, the REMP air sampling station in the plateyard (AP/CF-04) lost AC power. The out of service time did not impact the ability to collect sufficient sample volume over the collection cycle for this analysis. AR 02368123 was written to document and track this issue.

The third quarter TLD TL-41 (Portsmouth, NH) was found to be missing.

On November 24, 2020, the REMP air samplers in Exeter/Hampton (AP/CF-08), the Rock Pile (AP/CF-03), and Barge Landing (AP/CF-01) lost AC power. The out of service time did not impact the ability to collect sufficient sample volume over the collection cycle for this analysis. AR 02376558 was written to document and track this issue.

5.2 Comparison of Achieved LLDs with Requirements Table A.9.1-2 of the ODCM indicates the required Lower Limits of Detection (LLDs) for environmental sample analyses. (This table is duplicated in Table 5.2-1 of this report.) Occasionally an LLD for short-lived radionuclides is not achieved due to low sample volume or delays between sample collection and time of analysis. In such cases, ODCM Table A.9.1-2 requires a discussion of the event in the annual Radiological Environmental Operating Report.

For each analysis having an LLD requirement in ODCM Table A.9.1-2, the a posteriori (after the fact)

Minimum Detectable Concentration (MDC) calculated for that analysis was compared with the required LLD. During 2020, 1361 analyses had an LLD requirement listed in Table 5.2-1, and in all cases except

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four (three missed LLD's for 1-131 in milk, one missed LLD for Ba-140 in drinking water), the LLD requirements were met.

For the missed LLD's, the following explanations are provided:

LSN 519927001 (missed LLD for 1-131 in milk)-Sample was analyzed outside of the GEL holding time period, which is based on the short half-life of the isotope being analyzed.

LSN 523902001 (missed LLD for 1-131 in milk) - Sample was analyzed outside of the GEL holding time period, which is based on the short half-life of the isotope being analyzed.

LSN 527400001 (missed LLD for 1-131 in milk) - Sample was analyzed outside of the GEL holding time period, which is based on the short half-life of the isotope being analyzed.

LSN 506970003 (missed LLD for Ba-140 in drinking) -Analyst scheduling error.

The issue has been added into the laboratory NCR system for communication within the lab and process improvement.

5.3 Comparison of Results against Reporting Levels Seabrook Station ODCM Section 10.1 requires the notification of the NRC by special report within 30 days of receipt from the environmental laboratory whenever a Reporting Level in Table 5.3-1 is exceeded.

Reporting Levels are the environmental concentrations that relate to the ALARA design dose objectives of 10 CFR 50, Appendix I. It should be noted that environmental concentrations are averaged over calendar quarters for the purposes of this comparison, and that Reporting Levels apply only to measured levels of radioactivity due to plant effluents. During 2020, no Reporting Levels were exceeded.

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Table 5.2-1 DETECTION CAPABILITIES FOR ENVIRONMENTAL SAMPLE ANALYSIS 8 Lower Limit of Detection (LLD)

Fish and Water Airborne Particulate or Invertebrates Milk Food Products Sediment Analysis (pCi/kg) Gas (pCi/m 3 ) (pCi/kg, wet) (pCi/kg) (pCi/kg, wet) (pCi/kg, dry)

Gross Beta 4 0.01 H-3 3,000 Mn-54 15 130 Fe-59 30 260 Co-58, 60 15 130 Zn-65 30 260 Zr-Nb-95 15c 1-131 15 0.07 1 60b Cs-134 15 0.05 130 15 60 150 Cs-137 18 0.06 150 18 80 180 Ba-La-140 15c 15

a. Reference Seabrook Station ODCM, Table A.9.1-2 for clarifications.

b. Broad leaf vegetation only.

c. Parent only.

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Table 5.3-1 REPORTING LEVELS FOR RADIOACTIVITY CONCENTRATIONS IN ENVIRONMENTAL SAMPLESa Analysis Water Airborne Particulate or Gas Fish and Milk Food Products (pCi/kg) (pCi/m 3 ) Invertebrates (pCi/kg) (pCi/kg, wet)

(pCi/kg, wet)

H-3 30,000 Mn-54 1,000 30,000 Fe-59 400 10,000 Co-58 1,000 30,000 Co-60 300 10,000 Zn-65 300 20,000 Zr-Nb-95 400 1-131 100 0.9 3 100b Cs-134 30 10 1,000 60 1,000 Cs-137 50 20 2,000 70 2,000 Ba-La-140 200 300

a. Reference Seabrook Station ODCM Table A.9.1-3 for clarifications.

b. Broad leaf vegetation only.

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6.0 QUALITY ASSURANCE PROGRAM 6.1 GEL Laboratories QA GEL's primary goals are to ensure that all measurement data generated are scientifically and legally defensible, of known and acceptable quality per the data quality objectives (DQOs), and thoroughly documented to provide sound support for environmental decisions. In addition, GEL continues to ensure compliance with all contractual requirements, environmental standards, and regulations established by local, state and federal authorities.

GEL administers the QA program in accordance with their Quality Assurance Plan, GL-QS-B-001. The Quality Systems include all quality assurance (QA) policies and quality control (QC) procedures necessary to plan, implement, and assess the work that GEL performs. GEL's QA Program establishes a quality management system (QMS) that governs all of the activities of the organization.

The results of GEL's assessment of their laboratory activities listed in this section entails their quality assurance program for the proficiency testing (PT) and environmental monitoring aspects of GEL for 2020. GEL's QA Program is designed to monitor the quality of analytical processing associated with environmental, radiobioassay, effluent (10 CFR Part 50), and waste (10 CFR Part 61) sample analysis.

This summary was extracted from GEL Laboratories report entitled "2020 Annual Quality Assurance Report for the Radiological Environmental Monitoring Program (REMP)", dated February 26, 2021, and includes:

Intra-laboratory QC results analyzed during 2020.

Inter-laboratory QC results analyzed during 2020 where known values were available.

Quality Assurance Programs for Inter-laboratory, Intra-laboratory and Third Party Cross Check In addition to internal and client audits, GEL's laboratory participates in annual performance evaluation studies conducted by independent providers. GEL routinely participates in the following types of performance audits:

Proficiency testing and other inter-laboratory comparisons

Performance requirements necessary to retain Certifications

Evaluation of recoveries of certified reference and in-house secondary reference materials using statistical process control data.

Evaluation of relative percent difference between measurements through statistical process control (SPC) data.

GEL also participate in a number of proficiency testing programs for federal and state agencies and as required by contracts. It is GEL's policy that no proficiency evaluation samples be analyzed in any special manner. GEL's annual performance evaluation participation generally includes a combination of studies that support the following:

US Environmental Protection Agency (EPA) Discharge Monitoring Report, Quality Assurance Program (DMR-QA) - An annual national program sponsored by the EPA for laboratories engaged in the analysis of samples associated with the NPDES monitoring program. Participation is mandatory for all holders of NPDES permits. The permit holder must analyze for all of the parameters listed on the discharge permit. Parameters include general chemistry, metals, BOD/COD, oil and grease, ammonia, nitrates, etc.

Department of Energy (DOE) Mixed Analyte Performance Evaluation Program (MAPEP) - A semiannual program developed by DOE in support of DOE contractors performing waste

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analyses. Participation is required for all laboratories that perform environmental analytical measurements in support of environmental management activities. This program includes radioactive isotopes in water, soil, vegetation and air filters.

ERA's MRAD-Multimedia Radiochemistry Proficiency test program - This program is for labs seeking certification for radionuclides in wastewater and solid waste. The program is conducted in strict compliance with USEPA National Standards for Water Proficiency study.

ERA's lnterLab RadChem Proficiency Testing Program for radiological analyses - This program completes the process of replacing the USEPA EMSL-LV Nuclear Radiation Assessment Division program discontinued in 1998. Laboratories seeking certification for radionuclide analysis in drinking water also use the study. This program is conducted in strict compliance with the USEPA National Standards for Water Proficiency Testing Studies. This program encompasses Uranium by EPA method 200.8 (for drinking water certification in Utah/Primary NELAP), gamma emitters, Gross Alpha/Beta, lodine-131, naturally-occurring radioactive isotopes, Strontium-89/90, and Tritium.

ERA's Water Pollution (WP) biannual program for waste methodologies, which includes parameters for both organic and inorganic analytes.

ERA's Water Supply (WS) biannual program for drinking water methodologies, which includes parameters for organic and inorganic analytes.

Environmental Cross-Check Program administered by Eckert & Ziegler Analytics, Inc. - This program encompasses radionuclides in water, soil, milk, naturally-occurring radioactive isotopes in soil and air filters.

GEL procures single-blind performance evaluation samples from Eckert & Ziegler Analytics to verify the analysis of sample matrices processed at GEL. Samples are received on a quarterly basis. GEL's Third-Party Cross-Check Program provides environmental matrices encountered in a typical nuclear utility REMP. The Third-Party Cross-Check Program is intended to meet or exceed the inter-laboratory comparison program requirements discussed in NRC Regulatory Guide 4.15. Once performance evaluation samples have been prepared in accordance with the instructions provided by the program test (PT) provider, samples are managed and analyzed in the same manner as environmental samples from GEL's clients.

Quality Assurance Program for Internal and External Audits During each annual reporting period, at least one internal assessment of each area of the laboratory is conducted in accordance with the pre-established schedule from Standard Operating Procedure for the Conduct of Quality Audits, GL-QS-E-001. The annual internal audit plan is reviewed for adequacy and includes the scheduled frequency and scope of quality control actions necessary to GEL's QA program.

Internal audits are conducted at least annually in accordance with a schedule approved by the Quality Systems Director. Supplier audits are contingent upon the categorization of the supplier, and may or may not be conducted prior to the use of a supplier or subcontractor. Type I suppliers and subcontractors, regardless of how they were initially qualified, are re-evaluated at least once every three years.

In addition, prospective customers audit GEL during pre-contract audits. GEL hosts several external audits each year for both our clients and other programs. These programs include environmental monitoring, waste characterization, and radiobioassay. The following list of programs may audit GEL at least annually or up to every three years depending on the program.

TNI, The NELAC Institute, National Environmental Laboratory Accreditation Program (NELAP)

DOECAP, U.S. Department of Energy Consolidated Audit Program

DOELAP, U.S. Department of Energy Laboratory Accreditation Program

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DOE QSAS, U.S. Department of Energy, Quality Systems for Analytical Services

ISO/IEC 17025:2005

A2LA, American Association for Laboratory Accreditation

DOD ELAP, US Department of Defense Environmental Accreditation Program

NUPIC, Nuclear Procurement Issues Committee

South Carolina Department of Health and Environmental Control (SC DHEC)

The annual radiochemistry laboratory internal audit (20-RAD-001) was conducted in August and September, 2020. There were no findings or observations, and two recommendations for improvements from this assessment.

Performance Evaluation Acceptance Criteria for Environmental Sample Analysis GEL utilized an acceptance protocol based upon two performance models. For those inter-laboratory programs that already have established performance criteria for bias (i.e., MAPEP, and ERA/ELAP), GEL will utilize the criteria for the specific program. For intra-laboratory or third party quality control programs that do not have a specific acceptance criteria (i.e. the Eckert-Ziegler Analytics Environmental Cross-check Program), results will be evaluated in accordance with GEL's internal acceptance criteria.

Performance Evaluation Samples Performance Evaluation (PE) results and internal quality control sample results are evaluated in accordance with GEL acceptance criteria. The first criterion concerns bias, which is defined as the deviation of any one result from the known value. The second criterion concerns precision, which deals with the ability of the measurement to be replicated by comparison of an individual result with the mean of all results for a given sample set.

GEL also evaluates its analytical performance on a regular basis through statistical process control (SPC) acceptance criteria. Where feasible, this criterion is applied to both measures of precision and accuracy and is specific to sample matrix. GEL establishes environmental process control limits at least annually.

For Radiochemistry analysis, quality control evaluation is based on static limits rather than those that are statistically derived. Current process control limits are maintained in GEL's AlphaLIMS. GEL also measures precision with matrix duplicates and/or matrix spike duplicates. The upper and lower control limits (UCL and LCL respectively) for precision are plus or minus three times the standard deviation from the mean of a series of relative percent differences. The static precision criteria for radiochemical analyses are 0 - 20%, for activity levels exceeding the contract required detection limit (CRDL).

Quality Control Program for Environmental Sample Analysis GEL's internal QA Program is designed to include QC functions such as instrumentation calibration checks (to insure proper instrument response), blank samples, instrumentation backgrounds, duplicates, as well as overall staff qualification analyses and statistical process controls. Both quality control and qualification analyses samples are used to be as similar as the matrix type of those samples submitted for analysis by the various laboratory clients. These performance test samples (or performance evaluation samples) are either actual samples submitted in duplicate in order to evaluate the precision of laboratory measurements, or fortified blank samples, which have been given a known quantity of a radioisotope that is in the interest to GEL's clients.

Accuracy (or Bias) is measured through laboratory control samples and/or matrix spikes, as well as surrogates and internal standards. The UCLs and LCLs for accuracy are plus or minus three times the standard deviation from the mean of a series of recoveries. The static limit for radiochemical analyses is 75 - 125%. Specific instructions for out-of-control situations are provided in the applicable analytical SOP.

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GEL's Laboratory Control Standard (LCS) is an aliquot of reagent water or other blank matrix to which known quantities of the method analytes are added in the laboratory. The LCS is analyzed exactly like a sample, and its purpose is to determine whether the methodology is in control, and whether the laboratory is capable of making accurate and precise measurements. Some methods may refer to these samples as Laboratory Fortified Blanks (LFB). The requirement for recovery is between 75 and 125% for radiological analyses excluding drinking water matrix.

Bias (%) = (observed concentration)

100 %

(known concentration)

Precision is a data quality indicator of the agreement between measurements of the same property, obtained under similar conditions, and how well they conform to themselves. Precision is usually expressed as standard deviation, variance or range in either absolute or relative (percentage) terms.

GEL's laboratory duplicate (DUP or LCSD) is an aliquot of a sample taken from the same container and processed in the same manner under identical laboratory conditions. The aliquot is analyzed independently from the parent sample and the results are compared to measure precision and accuracy.

If a sample duplicate is analyzed, it will be reported as Relative Percent Difference (RPD). The RPD must be 20 percent or less, if both samples are greater than 5 times the MDC. If both results are less than 5 times MDC, then the RPD must be equal to or less than 100%. If one result is above the MDC and the other is below the MDC, then the RPD can be calculated using the MDC for the result of the one below the MDC. The RPD must be 100% or less. In the situation where both results are above the MDC but one result is greater than 5 times the MDC and the other is less than 5 times the MDC, the RPD must be less than or equal to 20%. If both results are below MDC, then the limits on % RPD are not applicable.

Difference(%)= (high duplicate result- low duplicate result)

100 %

(average of results)

Summary of Data Results During 2020, forty-five (45) radioisotopes associated with seven (7) matrix types were analyzed under GEL's Performance Evaluation program in participation with ERA, MAPEP, and Eckert & Ziegler Analytics. Matrix types were representative of client analyses performed during 2020. Of the four hundred fifty-six (456) total results reported, 97.1 % (443 of 456) were found to be acceptable. The list below contains the type of matrix evaluated by GEL.

Air Filter

Cartridge

Water

Milk

Soil

Liquid

Vegetation A summary list of all Inter-laboratory radiological proficiency test results and their evaluation against their acceptance criteria is provided in Table 6.1-1. This list reflects GEL's participation in the MAPEP Monitoring Program, the ERA MRaD PT Program, the ERA PT Program, and the Eckert & Ziegler Analytics Environmental Cross-Check Program.

Summaries of GEL's Intra-laboratory test result for bias and precision by sample matrix are provided in Table 6.1-3 (REMP Related) and Table 6.1-4 (All Samples).

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Summary of Participation in the Eckert & Ziegler Analytics Environmental Cross-Check Program Eckert & Ziegler Analytics provided samples for ninety-one (91) individual environmental analyses. The accuracy of each result reported to Eckert & Ziegler Analytics, Inc. is measured by the ratio of GEL's result to the known value. All results fell within GEL's acceptance criteria (100%). Table 6.1-2 list the results specific to the Eckert & Ziegler Analytics sample provided in 2020. No corrective action reports were noted for these results.

Summary of Participation in the MAPEP Monitoring Program MAPEP Series 42 and 43 were analyzed by the laboratory. Of the one hundred twenty-seven (127) analyses, 99% (126 out of 127) of all results fell within the PT provider's acceptance criteria. One isotope failure occurred in Series 40: lron-55 in soil. One isotope failure occurred in Series 43: lron-55 in soil.

For the corrective actions associated with MAPEP Series 42 and 43, refer to corrective action CARR201214-1296 (Table 6.1-5).

Summary of Participation in the ERA MRaD PT Program The ERA MRad program provided samples (MRAD-32 and MRAD-33) for one hundred ninety-eight (198) individual environmental analyses. One hundred ninety-four (194) of the 198 analyses fell within the PT provider's acceptance criteria (98%). Two isotope failures occurred in MRAD-32: Uranium-238 in air filter, Uranium-234 in water, and Uranium-Total in air filter.

For the corrective actions associated with MRAD-32 and MRAD-33, refer to corrective action CARR200902-1278 (Table 6.1-5).

Summary of Participation in the ERA PT Program The ERA program provided samples (RAD-120, RAD-121, and RAD-122) for forty (40) individual environmental analyses. Of the 40 analyses, 80% (32 out of 40) of all results fell within the PT provider's acceptance criteria. Three isotope failures occurred in RAD-120: Strontium-89, Tritium, and lodine-131 in water. Two failures occurred in RAD-122: Barium-133 and Cobalt-60 in water.

For the corrective actions associated with RAD-120 and RAD-122, refer to corrective actions CARR200224-1274 and CARR200902-1287, respectively (Table 6.1-5).

Corrective Action Request and Report (CARR)

There are two categories of corrective action at GEL. One is corrective action implemented at the analytical and data review level in accordance with the analytical standard operating procedures (SOP).

The other is formal corrective action documented by the Quality Systems Team in accordance with GEL's standard operating procedure GL-QS-E-002. A formal corrective action is initiated when a nonconformance reoccurs or is so significant that permanent elimination or prevention of the problem is required. Formal corrective action investigations include root cause analysis.

GEL includes quality requirements in most analytical standard operating procedures to ensure that data are reported only if the quality control criteria are met or the quality control measures that did not meet the acceptance criteria are documented. A formal corrective action is implemented according to GEL's standard operating procedure GL-QS-E-002 for Conducting Corrective/Preventive Action and Identifying Opportunities for Improvement. Recording and documentation is performed following guidelines stated in GEL's standard operating procedure GL-QS-E-012 for Client NCR Database Operation.

Any employee at GEL can identify and report a nonconformance and request that corrective action be taken. Any GEL employee can participate on a corrective action team as requested by the QS team or

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Group Leaders. The steps for conducting corrective action are detailed in GEL's standard operating procedure GL-QS-E-002. In the event that correctness or validity of the laboratory's test results in doubt, the laboratory will take corrective action. If investigations show that the results have been impacted, affected clients will be informed of the issue in writing within five (5) calendar days of the discovery.

Table 6.1-5 provides the status of CARRs for radiological performance testing during 2020. GEL has determined that causes of the failures did not impact any data reported to its clients.

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TABLE 6.1-1 2020 INTER-LAB RADIOLOGICAL PROFICIENCY TESTING RESULTS AND ACCEPTANCE CRITERIA PT Quarter I Analytical Sample GEL Known Acceptance Range/

Sample Number Unit Analyte I Nuclide Evaluation Provider Year Date Media Value value Ratio ERA 1st/2020 2124120 RAD-1 20 Water pCi/L Barium-133 59.2 64.5 53.7 - 71 .0 Acceptable ERA 1st/2020 2124120 RAD-120 Water pCi/L Cesium-134 21 .5 22.9 17.5 - 25.6 Acceptable ERA 1st12020 2124120 RAD-120 Water pCi/L Cesium-137 217 220 198 - 244 Acceptable ERA 1st12020 2124120 RAD-120 Water pCi/L Cobalt-60 97.7 91 .2 82.1 - 103 Acceptable ERA 1st/2020 2124120 RAD-120 Water pCi/L Zinc-65 332 298 268 - 348 Acceptable ERA 1st/2020 2/24/20 RAD-120 Water pCi/L Gross Alpha 67.1 58.9 30.8 - 73.3 Acceptable ERA 1st/2020 2124120 RAD-120 Water pCi/L Gross Alpha 55.4 58.9 30.8 - 73.3 Acceptable ERA 1st/2020 2124120 RAD-120 Water pCi/L Gross Beta 20 21 12.6 -29.1 Acceptable ERA 1st/2020 2124120 RAD-120 Water pCi/L Radium-226 15.6 17.4 12.9 - 19.9 Acceptable ERA 1st12020 2124120 RAD-120 Water pCi/L Radium-228 5.71 7.95 5.06 - 10.1 Acceptable ERA 1st/2020 2124120 RAD-120 Water pCi/L Radium-228 5.68 7.95 5.06 - 10.1 Acceptable ERA 1st/2020 2124120 RAD-120 Water pCi/L Uranium (Nat) 64.8 68.2 55.7 - 75.0 Acceptable ERA 1st/2020 2124120 RAD-120 Water pCi/L Tritium 15200 17800 15600 - 19600 Not Acceptable ERA 1st/2020 2/24/20 RAD-120 Water pCi/L Tritium 17700 17800 15600 - 19600 Acceptable ERA 1st/2020 2/24/20 RAD-120 Water pCi/L Strontium-89 73.3 59.3 47.6 - 67.1 Not Acceptable ERA 1st12020 2124120 RAD-120 Water pCi/L Strontium-89 70.8 59.3 47.6 - 67.1 Not Acceptable ERA 1st/2020 2124120 RAD-120 Water pCi/L Strontium-90 38.3 36.5 26.8 -42.1 Acceptable ERA 1st/2020 2124120 RAD-120 Water pCi/L Strontium-90 30.6 36.5 26.8 -42.1 Acceptable ERA 1st/2020 2124120 RAD-120 Water pCi/L lodine-131 23.7* 29.9 24.9 - 34 .9 Not Acceptable ERA 1st/2020 2124120 RAD-120 Water pCi/L lodine-131 31 .8 29.9 24.9 - 34.9 Acceptable EZA 1st12020 05/08/20 E13167 Cartridge pCi lodine-131 9.37E+01 9.12E+01 1.03 Acceptable EZA 1st12020 05/08/20 E13168 Milk pCi/L Strontium-89 9.15E+01 9.55E+01 0.96 Acceptable EZA 1st/2020 05/08/20 E13168 Milk pCi/L Strontium-90 1.51E+02 1.43E+02 0.62 Acceptable EZA 1st/2020 05/08/20 E13169 Milk pCi/L Cerium-1 41 1.99E+02 1.84E+02 1.08 Acceptable EZA 1st/2020 05/08/20 E13169 Milk pCi/L Cobalt-58 1.96E+02 1.89E+02 1.03 Acceptable EZA 1st/2020 05/08/20 E13169 Milk pCi/L Cobalt-60 2.33E+02 2.29E+02 1.02 Acceptable EZA 1st/2020 05/08/20 E13169 Milk pCi/L Chromium-5 1 3.84E+02 3.76E+02 1.02 Acceptable EZA 1st/2020 05/08/20 E13169 Milk pCi/L Cesium-134 1.36E+02 1.49E+02 0.91 Acceptable EZA 1st/2020 05/08/20 E13169 Milk pCi/L Cesium-137 1.91 E+02 1.80E+02 1.06 Acceptable EZA 1st/2020 05/08/20 E13169 Milk pCi/L Manganese-54 2.31 E+02 2.10E+02 1.1 Acceptable EZA 1st/2020 05/08/20 E13169 Milk pCi/L lron-59 1.82E+02 1.63E+02 1.12 Acceptable EZA 1st/2020 05/08/20 E13169 Milk pCi/L Zinc-65 2.69E+02 2.52E+02 1.07 Acceptable

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PT Quarter I Analytical Sample GEL Known Acceptance Range/

Sample Number Unit Analyte I Nuclide Evaluation Provider Year Date Media Value value Ratio EZA 1st/2020 05/08/20 E13170 Water pCi/L Cerium-141 2.11E+02 1.90E+02 1.1 1 Acceptable EZA 1st/2020 05/08/20 E13170 Water pCi/L Cesium-134 1.53E+02 1.54E+02 0.99 Acceptable EZA 1st/2020 05/08/20 E13170 Water pCi/L Cesium-137 2.08E+02 1.85E+02 1.12 Acceptable EZA 1st/2020 05/08/20 E131 70 Water pCi/L Chromium-5 1 4.34E+02 3.88E+02 1.12 Acceptable EZA 1st/2020 05/08/20 E13170 Water pCi/L Cobalt-58 2.21E+02 1.96E+02 1.13 Acceptable EZA 1st/2020 05/08/20 E13170 Water pCi/L Cobalt-60 2.59E+02 2.36E+02 1.10 Acceptable EZA 1st/2020 05/08/20 E13170 Water pCi/L lodine-131 1.02E+02 9.29E+01 1.1 Acceptable EZA 1st/2020 05/08/20 E13170 Water pCi/L lron-59 1.79E+02 1.68E+02 1.06 Acceptable EZA 1st/2020 05/08/20 E13170 Water pCi/L Manganese-54 2.48E+02 2.16E+02 1.15 Acceptable EZA 1st/2020 05/08/20 E13170 Water pCi/L Zinc-65 3.05E+02 2.61 E+02 1.17 Acceptable ERA 2nd/2020 05/19/20 MRAD-32 Soil pCi/kg Actinium-228 3200 3170 2090 - 3990 Acceptable ERA 2nd/2020 05/19/20 MRAD-32 Soil pCi/kg Actinium-228 3200 3170 2090 - 3990 Acceptable ERA 2nd/2020 05/19/20 MRAD-32 Soil pCi/kg Americium-241 1410 1730 934 - 2450 Acceptable ERA 2nd/2020 05/19/20 MRAD-32 Soil pCi/kg Bismuth-212 3160 3280 939 - 4890 Acceptable ERA 2nd/2020 05/19/20 MRAD-32 Soil pCi/kg Bismuth-212 3160 3280 939 - 4890 Acceptable ERA 2nd/2020 05/19/20 MRAD-32 Soil pCi/kg Bismuth-214 1870 2270 1090 - 3380 Acceptable ERA 2nd/2020 05/19/20 MRAD-32 Soil pCi/kg Bismuth-214 1870 2270 1090 - 3380 Acceptable ERA 2nd/2020 05/19/20 MRAD-32 Soil pCi/kg Cesium-134 5040 6200 4240- 7410 Acceptable ERA 2nd/2020 05/19/20 MRAD-32 Soil pCiikg Cesium-134 5040 6200 4240 - 7410 Acceptable ERA 2nd/2020 05/19/20 MRAD-32 Soil pCi/kg Cesium-137 6830 7280 5510 - 9210 Acceptable ERA 2nd/2020 05/19/20 MRAD-32 Soil pCi/kg Cesium-137 6830 7280 5510-9210 Acceptable ERA 2nd/2020 05/19/20 MRAD-32 Soil pCi/kg Cobalt-60 4840 5170 4070 - 6380 Acceptable ERA 2nd/2020 05/19/20 MRAD-32 Soil pCi/kg Cobalt-60 4840 5170 4070 - 6380 Acceptable ERA 2nd/2020 05/19/20 MRAD-32 Soil pCi/kg Lead-212 3580 3280 2290 - 4150 Acceptable ERA 2nd/2020 05/19/20 MRAD-32 Soil oCi/kQ Lead-212 3580 3280 2290 -4150 Acceotable ERA 2nd/2020 05/19/20 MRAD-32 Soil oCi/ka Lead-214 2380 2330 979 - 3660 Acceotable ERA 2nd/2020 05/19/20 MRAD-32 Soil oCi/ka Lead-214 2380 2330 979 - 3660 Acceotable ERA 2nd/2020 05/19/20 MRAD-32 Soil oCi/ka Manaanese-54 <25.4 <1000 <1000 Acceotable ERA 2nd/2020 05/19/20 MRAD-32 Soil oCi/ka Manaanese-54 <25.4 <1000 <1000 Acceotable ERA 2nd/2020 05/19/20 MRAD-32 Soil oCi/ka Plutonium-238 951 1010 504 - 1540 Acceptable ERA 2nd/2020 05/19/20 MRAD-32 Soil pCi/ka Plutonium-239 1020 1240 676 - 1780 Acceptable ERA 2nd/2020 05/19/20 MRAD-32 Soil pCi/ka Potassium-40 26000 24700 17000 - 29500 Acceptable ERA 2nd/2020 05/19/20 MRAD-32 Soil PCi/ka Potassium-40 26000 24700 17000 - 29500 Acceptable ERA 2nd/2020 05/19/20 MRAD-32 Soil pCi/kq Strontium-90 1980 2550 794 - 3970 Acceptable ERA 2nd/2020 05/19/20 MRAD-32 Soil pCi/kg Strontium-90 1980 2550 794 - 3970 Acceptable

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PT Quarter I Analytical Sample GEL Known Acceptance Range/

Sample Number Unit Analyte I Nuclide Evaluation Provider Year Date Media Value value Ratio ERA 2nd/2020 05/19/20 MRAD-32 Soil pCi/kg Strontium-90 1980 2550 794 - 3970 Acceotable ERA 2nd/2020 05/19/20 MRAD-32 Soil pCi/kg Thorium-234 5090 4010 1510-6870 Acceotable ERA 2nd/2020 05/19/20 MRAD-32 Soil pCi/kg Thorium-234 5090 4010 1510- 6870 Acceotable ERA 2nd/2020 05/19/20 MRAD-32 Soil pCi/kg Uranium-234 3330 3600 1690 - 4720 Acceotable ERA 2nd/2020 05/19/20 MRAD-32 Soil pCi/kg Uranium-234 3910 3600 1690 - 4720 Acceotable ERA 2nd/2020 05/19/20 MRAD-32 Soil pCi/kg Uranium-238 3490 3570 1960 - 4790 Acceotable ERA 2nd/2020 05/19/20 MRAD-32 Soil pCi/kg Uranium-238 2950 3570 1960 - 4790 Acceotable ERA 2nd/2020 05/19/20 MRAD-32 Soil oCi/ko Uranium-Total 6980 7340 4070 - 9490 Acceotable ERA 2nd/2020 05/19/20 MRAD-32 Soil pCi/kg Uranium-Total 6995 7340 4070 - 9490 Acceotable ERA 2nd/2020 05/19/20 MRAD-32 Soil µg/kg Uranium-Total (mass) 10500 10700 4830 - 14400 Acceptable ERA 2nd/2020 05/19/20 MRAD-32 Soil µg/kg Uranium-Total (mass) 8830 10700 4830 - 14400 Acceptable ERA 2nd/2020 05/19/20 MRAD-32 Soil oCi/kg Zinc-65 1070 1100 879 - 1500 Acceotable ERA 2nd/2020 05/19/20 MRAD-32 Soil oCi/kq Zinc-65 1070 1100 879 - 1500 Acceotable ERA 2nd/2020 05/19/20 MRAD-32 Vegetation pCi/kg Americium-241 3470 3950 2440 - 5580 Acceotable ERA 2nd/2020 05/19/20 MRAD-32 Vegetation pCi/kg Cesium-134 1780 2150 1430 - 2860 Acceotable ERA 2nd/2020 05/19/20 MRAD-32 Vegetation pCi/kg Cesium-134 1780 2150 1430 - 2860 Acceotable ERA 2nd/2020 05/19/20 MRAD-32 Veoetation pCi/kg Cesium-137 942 1030 792 - 1390 Acceotable ERA 2nd/2020 05/19/20 MRAD-32 Vegetation oCi/kg Cesium-137 942 1030 792 - 1390 Acceotable ERA 2nd/2020 05/19/20 MRAD-32 Vegetation oCi/ko Cobalt-60 987 997 783 - 1300 Acceptable ERA 2nd/2020 05/19/20 MRAD-32 Veaetation oCi/ko Cobalt-60 987 997 783 - 1300 Acceotable ERA 2nd/2020 05/19/20 MRAD-32 Veqetation oCi/kq Curium-244 881 1050 592 - 1310 Acceotable ERA 2nd/2020 05/19/20 MRAD-32 Veqetation pCi/kg Manganese-54 <39.6 <300 <300 Acceotable ERA 2nd/2020 05/19/20 MRAD-32 Vegetation pCi/kq Manganese-54 <39.6 <300 <300 Acceotable ERA 2nd/2020 05/19/20 MRAD-32 Vegetation pCi/kg Plutonium-238 1070 1150 796 - 1480 Acceotable ERA 2nd/2020 05/19/20 MRAD-32 Vegetation pCi/kg Plutonium-239 227 232 160- 294 Acceotable ERA 2nd/2020 05/19/20 MRAD-32 Veoetation oCi/ko Potassium-40 35700 39300 29500 - 49800 Acceotable ERA 2nd/2020 05/19/20 MRAD-32 Veoetation oCi/ko Potassium-40 35700 39300 29500 - 49800 Acceotable ERA 2nd/2020 05/19/20 MRAD-32 Veqetation oCi/ko Strontium-90 1720 1720 970 - 2240 Acceotable ERA 2nd/2020 05/19/20 MRAD-32 Veqetation oCi/kq Strontium-90 1720 1720 970 - 2240 Acceotable ERA 2nd/2020 05/19/20 MRAD-32 Veqetation oCi/kq Strontium-90 1720 1720 970 - 2240 Acceotable ERA 2nd/2020 05/19/20 MRAD-32 Veqetation oCi/kg Uranium-234 1750 1900 1330 - 2420 Acceotable ERA 2nd/2020 05/19/20 MRAD-32 Veqetation oCi/ko Uranium-238 1780 1880 1330 - 2350 Acceotable ERA 2nd/2020 05/19/20 MRAD-32 Veqetation oCi/kq Uranium-Total 3620 3870 2470 - 5220 Acceotable ERA 2nd/2020 05/19/20 MRAD-32 Vegetation µg/kg Uranium-Total (mass) 5330 5640 4330 - 6990 Acceptable ERA 2nd/2020 05/19/20 MRAD-32 Vegetation pCi/kg Zinc-65 2740 2750 2050 - 4080 Acceptable ERA 2nd/2020 05/19/20 MRAD-32 Veoetation pCi/kg Zinc-65 2740 2750 2050 - 4080 Acceptable ERA 2nd/2020 05/19/20 MRAD-32 Air Filter oCi/Filter Americium-241 64.9 74.7 53.3 - 99.6 Acceotable ERA 2nd/2020 05/19/20 MRAD-32 Air Filter oCi/Filter Cesium-134 1360 1390 902 - 1700 Acceotable

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PT Quarter I Analytical Sample GEL Known Acceptance Range/

Sample Number Unit Analyte I Nuclide Evaluation Provider Year Date Media Value value Ratio ERA 2nd/2020 05/19/20 MRAD-32 Air Filter pCi/Filter Cesium-134 1360 1390 902 - 1700 Acceptable ERA 2nd/2020 05/19/2 0 MRAD-32 Air Filter pCi/Filter Cesium-137 370 351 288 - 460 Acceptable ERA 2nd/2020 05/19/20 MRAD-32 Air Filter pCi/Filter Cesium-137 370 351 288 - 460 Acceptable ERA 2nd/2020 05/1 9/20 MRAD-32 Air Filter pCi/Filter Cobalt-60 459 422 359 - 536 Acceptable ERA 2nd/2020 05/19/20 MRAD-32 Air Filter pCi/Filter Cobalt-60 459 422 359 - 536 Acceptable ERA 2nd/2020 05/19/2 0 MRAD-32 Air Filter pCi/Filter lron-55 1150 1260 460-2010 Acceptable ERA 2nd/2020 05/19/2 0 MRAD-32 Air Filter pCi/Filter Manganese-54 <3.87 <50.0 <50.0 Acceptable ERA 2nd/2020 05/19/2 0 MRAD-32 Air Filter PCi/Filter Manaanese-54 <3.87 <50.0 <50.0 Acceptable ERA 2nd/2020 05/19/20 MRAD-32 Air Filter PCi/Filter Plutonium-238 21.9 28 21.1 - 34.4 Acceptable ERA 2nd/2020 05/19/2 0 MRAD-32 Air Filter pCi/Filter Plutonium-239 30.6 40.1 30.0 - 48.4 Acceptable ERA 2nd/2020 05/19/2 0 MRAD-32 Air Filter pCi/Filter Strontium-90 181 175 111 -238 Acceptable ERA 2nd/2020 05/19/2 0 MRAD-32 Air Filter pCi/Filter Uranium-234 45.7 56 .2 41 .7-65.9 Acceptable ERA 2nd/2020 05/19/20 MRAD-32 Air Filter PCi/Filter Uranium-234 46 .7 56.2 41.7 - 65.9 Acceptable ERA 2nd/2020 05/19/20 MRAD-32 Air Filter pCi/Filter Uranium-238 46 55 .7 42 .1 - 66.5 Acceptable ERA 2nd/2020 05/19/20 MRAD-32 Air Filter pCi/Filter Uranium-238 39.6 55 .7 42.1 - 66.5 Not Acceptable ERA 2nd/2020 05/19/20 MRAD-32 Air Filter PCi/Filter Uranium-Total 94.5 114 83.2- 135 Acceptable ERA 2nd/2020 05/19/20 MRAD-32 Air Filter PCi/Filter Uranium-Total 88.1 114 83.2 - 135 Acceptable ERA 2nd/2020 05/19/20 MRAD-32 Air Filter µg/Filter Uranium-Total (mass) 138 167 134- 196 Acceptable ERA 2nd/2020 05/19/20 MRAD-32 Air Filter µg/Filter Uranium-Total (mass) 118 167 134 - 196 Not Acceptable ERA 2nd/2020 05/19/2 0 MRAD-32 Air Filter PCi/Filter Zinc-65 798 694 569 - 1060 Acceptable ERA 2nd/2020 05/19/20 MRAD-32 Air Filter pCi/Filter Zinc-65 798 694 569- 1060 Acceptable ERA 2nd/2020 05/19/20 MRAD-32 Air Filter pCi/Filter Gross Alpha 34.4 29 .3 15.3 - 48.3 Acceptable ERA 2nd/2020 05/19/20 MRAD-32 Air Filter pCi/Filter Gross Beta 61.1 66.4 40.3 - 100 Acceptable ERA 2nd/2020 05/19/2 0 MRAD-32 Water pCi/L Americium-241 47 .9 45 .3 31.1 - 57 .9 Acceptable ERA 2nd/2020 05/19/2 0 MRAD-32 Water pCi/L Cesium-1 34 1420 1520 1150- 1670 Acceptable ERA 2nd/2020 05/19/2 0 MRAD-32 Water pCi/L Cesium-1 34 1420 1520 1150-1670 Acceptable ERA 2nd/2020 05/19/2 0 MRAD-32 Water pCi/L Cesium-1 34 1420 1520 1150-1670 Acceptable ERA 2nd/2020 05/19/2 0 MRAD-32 Water pCi/L Cesium-137 2440 2390 2050- 2720 Acceptable ERA 2nd/2020 05/19/20 MRAD-32 Water pCi/L Cesium-137 2440 2390 2050 - 2720 Acceptable ERA 2nd/2020 05/19/2 0 MRAD-32 Water pCi/L Cesium-137 2440 2390 2050 - 2720 Acceptable ERA 2nd/2020 05/19/20 MRAD-32 Water pCi/L Cobalt-60 2890 2760 2380 - 3170 Acceptable ERA 2nd/2020 05/19/2 0 MRAD-32 Water pCi/L Cobalt-60 2890 2760 2380 - 3170 Acceptable ERA 2nd/2020 05/19/2 0 MRAD-32 Water PCi/L Cobalt-60 2890 2760 2380 - 3170 Acceptable ERA 2nd/2020 05/19/20 MRAD-32 Water PCi/L lron-55 140 152 89.3 - 221 Acceptable ERA 2nd/2020 05/19/20 MRAD-32 Water pCi/L Manaanese-54 <6. 25 <100 <100 Acceptable ERA 2nd/2020 05/1 9/20 MRAD-32 Water pCi/L Manaanese-54 <6.25 <100 <100 Acceptable ERA 2nd/2020 05/19/20 MRAD-32 Water pCi/L Manganese-54 <6.25 <100 <100 Acceptable ERA 2nd/2020 05/19/20 MRAD-32 Water pCi/L Plutonium-238 32.5 36.4 21.9-47.2 Acceptable

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PT Quarter I Analytical Sample GEL Known Acceptance Range/

Sample Number Unit Analyte I Nuclide Evaluation Provider Year Date Media Value value Ratio ERA 2nd/2020 05/19/20 MRAD-32 Water pCi/L Plutonium-239 29.7 33.6 20.8 - 41 .4 Acceotable ERA 2nd/2020 05/19/20 MRAD-32 Water pCi/L Strontium-90 426 447 322 - 552 Acceotable ERA 2nd/2020 05/19/20 MRAD-32 Water pCi/L Uranium-234 187 186 142 - 213 Acceotable ERA 2nd/2020 05/19/20 MRAD-32 Water pCi/L Uranium-234 226* 186 142 -21 3 Not Acceptable ERA 2nd/2020 05/19/20 MRAD-32 Water oCi/L Uranium-238 191 184 143 - 217 Acceotable ERA 2nd/2020 05/19/20 MRAD-32 Water oCi/L Uranium-238 199 184 143 - 2 17 Acceotable ERA 2nd/2020 05/19/20 MRAD-32 Water oCi/L Uranium-Total 387 378 295 - 431 Acceotable ERA 2nd/2020 05/19/20 MRAD-32 Water pCi/L Uranium-Tota l 434.3* 378 295 - 431 Not Acceptable ERA 2nd/2020 05/19/20 MRAD-32 Water µg/L Uranium-Total (mass) 572 551 446 - 625 Acceptable ERA 2nd/2020 05/19/20 MRAD-32 Water µg/L Uranium-Total (mass) 595 551 446 - 625 Acceptable ERA 2nd/2020 05/19/20 MRAD-32 Water pCi/L Zinc-65 1330 11 90 1060 - 1500 Acceotable ERA 2nd/2020 05/19/20 MRAD-32 Water oCi/L Zinc-65 1330 1190 1060 -1500 Acceotable ERA 2nd/2020 05/19/20 MRAD-32 Water pCi/L Zinc-65 1330 1190 1060 - 1500 Acceotable ERA 2nd/2020 05/19/20 MRAD-32 Water pCi/L Gross Alpha 67.6 165 60.2 - 228 Acceotable ERA 2nd/2020 05/19/20 MRAD-32 Water pCi/L Gross Alpha 67.6 165 60.2 - 228 Acceptable ERA 2nd/2020 05/19/20 MRAD-32 Water pCi/L Gross Beta 143 158 79.0 -217 Acceptable ERA 2nd/2020 05/19/20 MRAD-32 Water oCi/L Gross Beta 143 158 79.0 - 217 Acceotable ERA 2nd/2020 05/19/20 MRAD-32 Water oCi/L Tritium 5990 6280 4730 - 7640 Acceotable ERA 2nd/2020 05/26/20 RAD-121 Water oCi/L Tritium 13100 14100 12300 - 15500 Acceotable ERA 2nd/2020 05/26/20 RAD-121 Water pCi/L Strontium-89 68.8 60.1 48.3 - 67.9 Not Acceptable ERA 2nd/2020 05/26/20 RAD-121 Water pCi/L Strontium-89 71.6 60.1 48.3 - 67.9 Not Acceptable ERA 2nd/2020 05/26/20 RAD-121 Water oCi/L lodine-131 27.5 28.9 24.1 - 33.8 Acceotable MAPEP 2nd/2020 07102120 MAPEP GrF42 Filter Bq/sample Gross alpha 0.79 1.24 0.37-2.11 Acceptable MAPEP 2nd/2020 07/02/20 MAPEP GrF42 Filter Bq/sample Gross beta 1.84 2.00 1.00-3.00 Acceptable MAPEP 2nd/2020 07/02/20 MAPEP-20-GrW42 Water Bq/L Gross alpha 1.01 1.03 0.31-1.75 Acceptable MAPEP 2nd/2020 07102120 MAPEP-20-GrW42 Water Bq/L Gross beta 4.18 4 .24 2.1 2-6.36 Acceptable MAPEP 2nd/2020 07/02/20 MAPEP MaS42 Soil Bq/Kg Americium-241 43.0 40.9 28.6-53.2 Acceptable MAPEP 2nd/2020 07102120 MAPEP MaS42 Soil Bq/Kg Cesium- 134 984 1114 780-1 448 Acceptable MAPEP 2nd/2020 07102120 MAPEP MaS42 Soil Bq/Kg Cesium-137 1060 1020 71 4-1326 Acceptable MAPEP 2nd/2020 07102120 MAPEP MaS42 Soil Bq/Kg Cobalt-57 1200.000 1071 750-1392 Acceptable MAPEP 2nd/2020 07102120 MAPEP-20-MaS42 Soil Bq/Kg Cobalt-60 0.366 False Pos Test Acceptable MAPEP 2nd/2020 07102120 MAPEP-20-MaS42 Soil Bq/Kg lron-55 950.0 1096 767-1425 Acceptable MAPEP 2nd/2020 07/02/20 MAPEP-20-MaS42 Soil Bq/Kg Manganese-54 961 945 662-1 229 Acceptable MAPEP 2nd/2020 07102120 MAPEP MaS42 Soil Bq/Kg Nickel-63 -0.727 False Pos Test Acceptable MAPEP 2nd/2020 07102120 MAPEP MaS42 Soil Bq/Kg Plutonium-238 38.0 41 .8 29.3-54.3 Acceptable MAPEP 2nd/2020 07/02/20 MAPEP MaS42 Soil Bq/Kg Plutonium-239/240 38.0 41 .8 29.3-54.3 Acceptable MAPEP 2nd/2020 07/02/20 MAPEP MaS42 Soil Bq/Kg Potassium-40 618 625 438-81 3 Acceptable MAPEP 2nd/2020 07/02/20 MAPEP-20-MaS42 Soil Bq/Kg Strontium-90 286 340 238-442 Acceptable MAPEP 2nd/2020 07102120 MAPEP-20-MaS42 Soil Bq/Kg Technetium-99 728 706 494-918 Acceptable

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PT Quarter I Analytical Sample GEL Known Acceptance Range/

Sample Number Unit Analyte I Nuclide Evaluation Provider Year Date Media Value value Ratio MA PEP 2nd/2020 07102120 MAPEP MaS42 Soil Sq/Kg U-234/233 43 .2 40 .3 28.2-52.4 Acceptable MA PEP 2nd/2020 07102120 MAPEP MaS42 Soil Sq/Kg Uranium-238 64 .6 68 .0 48-88 Acceptable MA PEP 2nd/2020 07102120 MAPEP MaS42 Soil Sq/Kg Zinc-65 784 751 526-976 Acceptable MA PEP 2nd/2020 07102120 MAPEP MaW42 Water Sq/L Americium-241 0.545 0.547 0.383-0.711 Acceptable MA PEP 2nd/2020 07102120 MAPEP-20-MaW42 Water Sq/L Cesium-134 17.0 18.5 13.0-24 .1 Acceptable MA PEP 2nd/2020 07102120 MAPEP-20-MaW42 Water Sq/L Cesium-137 12.0 11 .3 7.9-14 .7 Acceptable MAPEP 2nd/2020 07102120 MAPEP MaW42 Water Sq/L Cobalt-57 19.7 19.7 13.8-25 .6 Acceptable MAPEP 2nd/2020 07102120 MAPEP MaW42 Water Sq/L Cobalt-60 11 .0 10.6 7.4-13 .8 Acceptable MA PEP 2nd/2020 07/02/20 MAPEP MaW42 Water Sq/L Hydrogen-3 193 196 137-255 Acceptable MA PEP 2nd/2020 07102120 MAPEP MaW42 Water Sq/L lron-55 18.2 17.8 12.5-23.1 Acceptable MA PEP 2nd/2020 07102120 MAPEP-20-MaW42 Water Sq/L Manganese-54 20.6 19.6 13.7-25.5 Acceptable MAPEP 2nd/2020 07102120 MAPEP-20-MaW42 Water Sq/L Nickel-63 14.1 11 .1 7.8-14.4 Acceptable MAPEP 2nd/2020 07102120 MAPEP MaW42 Water Sq/L Plutonium-238 0.822 0.940 0.66-1 .22 Acceptable MAPEP 2nd/2020 07102120 MAPEP MaW42 Water Sq/L Plutonium-239/240 0.686 0.737 0.516-0 .958 Acceptable MAPEP 2nd/2020 07102120 MAPEP MaW42 Water Sq/L Potassium-40 -0 .0485 False Pos Test Acceptable MAPEP 2nd/2020 07102120 MAPEP MaW42 Water Sq/L Radium-226 0.366 0.365 0.256-0.475 Acceptable MA PEP 2nd/2020 07102120 MAPEP-20-MaW42 Water Sq/L Strontium-90 0.0122 False Pos Test Acceptable MA PEP 2nd/2020 07102120 MAPEP-20-MaW42 Water Sq/L Technetium-99 3.72 3.63 2.54-4 .72 Acceptable MA PEP 2nd/2020 07102120 MAPEP MaW42 Water Sq/L Uranium-234 1.02 0.97 0.68-1 .26 Acceptable MA PEP 2nd/2020 07102120 MAPEP-20-MaW42 Water Sq/L Uranium-238 0.98 0.95 0.67-1 .24 Acceptable MA PEP 2nd/2020 07102120 MAPEP-20-MaW42 Water Sq/L Zinc-65 23.9 22.2 15.5-28 .9 Acceptable MAPEP 2nd/2020 07102120 MAPEP XaW42 Alk . Water Sq/L lodine-129 1.01 1.001 0.701-1 .301 Acceptable MAPEP 2nd/2020 07102120 MAPEP RdF42 Filter ug/sample Uranium-235 0.0438 0.0460 0.0322-0.0598 Acceptable MAPEP 2nd/2020 07102120 MAPEP RdF42 Filter ug/sample Uranium-238 6.39 6.3 4.4-8 .2 Acceptable MAPEP 2nd/2020 07/02/20 MAPEP RdF42 Filter ug/sample Uranium-Total 6.43 6.3 4.4-8 .2 Acceptable MAPEP 2nd/2020 07102120 MAPEP-20-RdF42 Filter Sq/sample Americium-241 0.0671 0.0675 0.0473-0.0878 Acceptable MAPEP 2nd/2020 07102120 MAPEP-20-RdF42 Filter Sq/sample Cesium-134 0.626 0.600 0.420-0.780 Acceptable MAPEP 2nd/2020 07102120 MAPEP-20-RdF42 Filter Sq/sample Cesium-137 0.802 0.735 0.515-0.956 Acceptable MA PEP 2nd/2020 07102120 MAPEP RdF42 Filter Sq/sample Cobalt-57 1.54 1.50 1.05-1 .95 Acceptable MA PEP 2nd/2020 07102120 MAPEP RdF42 Filter Sq/sample Cobalt-60 1.29 1.23 0.86-1 .60 Acceptable MA PEP 2nd/2020 07102120 MAPEP RdF42 Filter Sq/sample Manganese-54 0.0065 False Pos Test Acceptable MA PEP 2nd/2020 07102120 MAPEP-20-RdF42 Filter Sq/sample Plutonium-238 0.0341 0.0348 0.0244-0 .0452 Acceptable MA PEP 2nd/2020 07102120 MAPEP-20-RdF42 Filter Sq/sample Plutonium-239/240 0.0395 0.0379 0.0265-0 .0493 Acceptable MA PEP 2nd/2020 07102120 MAPEP-20-RdF42 Filter Sq/sample Strontium-90 0.884 0.97 0.68-1 .26 Acceptable MA PEP 2nd/2020 07102120 MAPEP RdF42 Filter Sq/sample Uranium-234 0.0788 0.075 0.053-0 .098 Acceptable MA PEP 2nd/2020 07102120 MAPEP RdF42 Filter Sq/sample Uranium-238 0.0801 0.078 0.055-0 .101 Acceptable MA PEP 2nd/2020 07/02/20 MAPEP RdF42 Filter Bq/sample Zinc-65 1.43 1.18 0.83-1 .53 Acceptable MA PEP 2nd/2020 07102120 MAPEP RdV42 Vegetation Bq/sample Americium-241 0.0761 0.075 0.053-0 .098 Acceptable MA PEP 2nd/2020 07102120 MAPEP-20-RdV42 Vegetation Bq/sample Cesium-134 3.55 3.82 2.67-4.97 Acceptable MA PEP 2nd/2020 07102120 MAPEP-20-RdV42 Vegetation Bq/sample Cesium-137 2.83 2.77 1.94-3.60 Acceptable

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PT Quarter I Analytical Sample GEL Known Acceptance Range/

Sample Number Unit Analyte I Nuclide Evaluation Provider Year Date Media Value value Ratio MAPEP 2nd/2020 07102120 MAPEP RdV42 Vegetation Bq/sample Cobalt-57 0.00561 False Pos Test Acceptable MAPEP 2nd/2020 07102120 MAPEP RdV42 Vegetation Bq/sample Cobalt-60 2.84 2.79 1.95-3.63 Acceptable MAPEP 2nd/2020 07102120 MAPEP RdV42 Vegetation Bq/sample Manganese-54 4.74 4.58 3.21-5.95 Acceptable MAPEP 2nd/2020 07102120 MAPEP RdV42 Vegetation Bq/sample Plutonium-238 0.0447 0.0472 0.0330-0.0614 Acceptable MAPEP 2nd/2020 07102120 MAPEP-20-RdV42 Vegetation Bq/sample Plutonium-239/240 0.06950 0.0772 0.0540-0.1 004 Acceptable MAPEP 2nd/2020 07102120 MAPEP-20-RdV42 Vegetation Bq/sample Stronlium-90 0.361 0.492 0.344-0.640 Acceptable MAPEP 2nd/2020 07102120 MAPEP RdV42 Vegetation Bq/sample Uranium-234 0.1070 0.102 0.071-0.133 Acceptable MAPEP 2nd/2020 07102120 MAPEP RdV42 Vegetation Bq/sample Uranium-238 0.1150 0.1 03 0.072-0.134 Acceptable MAPEP 2nd/2020 07102120 MAPEP RdV42 Vegetation Bq/sample Zinc-65 4.14 3.79 2.65-4.93 Acceptable EZA 2nd/2020 07/31/20 E13171 Cartridge pCi lodine-131 9.68E+01 9.19E+01 1.05 Acceptable EZA 2nd/2020 07/31/20 E13172 Milk pCi/L Strontium-89 8.67E+0 1 8.81E+01 0.98 Acceptable EZA 2nd/2020 07/31/20 E13172 Milk PCi/L Strontium-90 1.06E+01 1.27E+01 0.83 Acceptable EZA 2nd/2020 07/31/20 E13173 Milk pCi/L Cerium-141 1.29E+02 1.16E+02 1.11 Acceptable EZA 2nd/2020 07/31/20 E13173 Milk pCi/L Cobalt-58 1.04E+02 1.00E+02 1.03 Acceptable EZA 2nd/2020 07/31/20 E13173 Milk pCi/L Cobalt-60 2.00E+02 1.95E+02 1.02 Acceptable EZA 2nd/2020 07/31/20 E13173 Milk pCi/L Chromium-51 2.91E+02 2.56E+02 1.14 Acceptable EZA 2nd/2020 07/31/20 E13173 Milk pCi/L Cesium-134 1.40E+02 1.46E+02 0.96 Acceptable EZA 2nd/2020 07/31/20 E13173 Milk oCi/L Cesium-137 1.09E+02 1.04E+02 1.05 Acceotable EZA 2nd/2020 07/31/20 E13173 Milk pCi/L lron-59 1.09E+02 1.01E+02 1.08 Acceptable EZA 2nd/2020 07/31/20 E13173 Milk pCi/L lodine-131 8.31 E+0 1 8.15E+01 1.02 Acceptable EZA 2nd/2020 07/31/20 E13173 Milk pCi/L Manoanese-54 1.41E+02 1.34E+02 1.05 Acceptable EZA 2nd/2020 07/31/20 E13173 Milk pCi/L Zinc-65 2.48E+02 2.25E+02 1.10 Acceptable EZA 2nd/2020 07/31/20 E13174 Water pCi/L Cerium-141 1.23E+02 1.17E+02 1.05 Acceptable EZA 2nd/2020 07/31/20 E13174 Water pCi/L Cobalt-58 1.05E+02 1.02E+02 1.03 Acceptable EZA 2nd/2020 07/31/20 E13174 Water pCi/L Cobalt-60 2.05E+02 1.98E+02 1.04 Acceptable EZA 2nd/2020 07/31/20 E13174 Water pCi/L Chromium-51 2.76E+02 2.59E+02 1.06 Acceptable EZA 2nd/2020 07/31/20 E13174 Water pCi/L Cesium-134 1.36E+02 1.48E+02 0.92 Acceptable EZA 2nd/2020 07/31/20 E13174 Water pCi/L Cesium-137 1.04E+02 1.05E+02 0.99 Acceptable EZA 2nd/2020 07/31/20 E13174 Water pCi/L lron-59 1.05E+02 1.02E+02 1.03 Acceptable EZA 2nd/2020 07/31/20 E13174 Water pCi/L lodine-131 9.10E+01 8.05E+01 1.13 Acceptable EZA 2nd/2020 07/31/20 E13174 Water pCi/L Manoanese-54 1.47E+02 1.35E+02 1.09 Acceptable EZA 2nd/2020 07/31/20 E13174 Water pCi/L Zinc-65 2.49E+02 2.27E+02 1.10 Acceptable ERA 3rd /2020 08124120 RAD -122 Water pCi/L Barium-133 64.7 58.6 48.6 - 64.6 Not Acceptable ERA 3rd /2020 08124120 RAD-122 Water pCi/L Cesium-1 34 23 22.3 17.0 - 25.0 Acceotable ERA 3rd /2020 08/24/20 RAD-122 Water pCi/L Cesium-137 76.5 73 65.7 - 83.0 Acceptable ERA 3rd /2020 08124120 RAD - 122 Water pCi/L Cobalt-60 97.9 86.1 77.5 - 97.0 Not Acceptable ERA 3rd /2020 08124120 RAD - 122 Water pCi/L Zinc-65 96.3 82.9 74.6 - 99.6 Acceotable ERA 3rd /2020 08/24/20 RAD-122 Water oCi/L Gross Aloha 54.3 52.4 27.3 - 65.6 Acceptable ERA 3rd /2020 08/24/20 RAD - 122 Water oCi/L Gross Beta 24.7 24.3 15.0 - 32.3 Acceptable

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PT Quarter I Analytical Sample GEL Known Acceptance Range/

Sample Number Unit Analyte I Nuclide Evaluation Provider Year Date Media Value value Ratio ERA 3rd /2020 08/24/2 0 RAD-122 Water pCi/L Radium-226 9.42 10.8 8.08 - 12.5 Acceptable ERA 3rd /2020 08/24/2 0 RAD-122 Water pCi/L Radium-228 5.55 5.42 3.28 - 7.19 Acceptable ERA 3rd /2020 08/24/20 RAD -122 Water pCi/L Uranium (Nat) 28.9 29.3 23.7 - 32.5 Acceptable ERA 3rd /2020 08/24/2 0 RAD -122 Water pCi/L Uranium (Nat)mass 41 .3 42.7 34.5 - 47.4 Acceptable ERA 3rd /2020 08/24/20 RAD-122 Water pCi/L Tritium 17800 20300 17800 - 22300 Acceptable ERA 3rd /2020 08/24/2 0 RAD- 122 Water µQ/L Tritium 20200 20300 17800 - 22300 Acceptable ERA 3rd /2020 08/24/20 RAD-122 Water pCi/L Strontium-89 61 .7 68.9 56 .2 - 77 .1 Accepta ble ERA 3rd /2020 08/24/20 RAD-122 Water pCi/L Strontium-90 18.2 19.5 13.9 - 23.1 Acceptable ERA 3rd /2020 08/24/20 RAD-122 Water pCi/L lodine-131 29.9 26.1 21.7 - 30.8 Acceptable EZA 3rd/2020 11 /10/20 E13175 Cartridge pCi lodine-1 31 7.96E+01 7.67E+01 1.04 Acceptable EZA 3rd/2020 11/10/20 E13176 Milk pCi/L Strontium-89 1.13E+02 9.54E+01 1.18 Acceptable EZA 3rd/2020 11 /1 0/2 0 E13176 Milk PCi/L Strontium-90 9.47E+01 1.28E+02 0.74 Acceptable EZA 3rd/2020 11 /10/2 0 E13177 Milk pCi/L Cerium-141 1.47E+02 1.50E+02 0.98 Acceptable EZA 3rd/2020 11 /10/2 0 E13177 Milk pCi/L Cobalt-58 1.81 E+02 1.80E+02 1.01 Acceptable EZA 3rd/2020 11 /10/2 0 E13177 Milk pCi/L Cobalt-60 3.85E+02 3.79E+02 1.02 Acceptable EZA 3rd/2020 11 /10/2 0 E1 3177 Milk PCi/L Chromium-51 4.11E+02 3.72E+02 1.10 Acceptable EZA 3rd/2020 11 /10/2 0 E13177 Milk PCi/L Cesium-134 1.82E+02 2.00E+02 0.91 Acceptable EZA 3rd/2020 11 /10/2 0 E13177 Milk pCi/L Cesium-1 37 2.58E+02 2.50E+02 1.03 Acceptable EZA 3rd/2020 11 /10/2 0 E13177 Milk pCi/L lron-59 2.29E+02 2.00E+02 1.14 Acceptable EZA 3rd/2020 11 /10/2 0 E13177 Milk pCi/L lodine-1 31 9.49E+01 9.50E+01 1.00 Acceptable EZA 3rd/2020 11/10/20 E13177 Milk pCi/L ManQanese-54 1.96E+02 1.80E+02 1.09 Acceptable EZA 3rd/2020 11 /1 0/2 0 E13177 Milk pCi/L Zinc-65 3.04E+02 2.70E+02 1.13 Acceptable EZA 3rd/2020 11 /10/2 0 E13178 Water pCi/L Cerium-141 1.58E+02 1.51 E+02 1.05 Acceptable EZA 3rd/2020 11 /10/2 0 E13178 Water PCi/L Cobalt-58 1.90E+02 1.80E+02 1.05 Acceptable EZA 3rd/2020 11 /10/2 0 E13178 Water pCi/L Cobalt-60 4.04E+02 3.80E+02 1.06 Acceptable EZA 3rd/2020 11 /10/2 0 E13178 Water pCi/L Chromium-51 3.45E+02 3.73E+02 0.92 Acceptable EZA 3rd/2020 11 /1 0/2 0 E13178 Water pCi/L Cesium-134 1.81E+02 2.01E+02 0.9 Acceptable EZA 3rd/2020 11 /10/2 0 E13178 Water pCi/L Cesium-137 2.63E+02 2.51E+02 1.05 Acceptable EZA 3rd/2020 11 /10/2 0 E13178 Water pCi/L lron-59 2.26E+02 2.01E+02 1.12 Acceptable EZA 3rd/2020 11 /10/2 0 E13178 Water pCi/L lodine-131 9.80E+01 9.82E+01 1.00 Acceptable EZA 3rd/2020 11 /1 0/20 E1 3178 Water pCi/L ManQanese-54 2.06E+02 1.81E+02 1.14 Acceptable EZA 3rd/2020 11/10/20 E1 3178 Water pCi/L Zinc-65 3.02E+02 2.71E+02 1.12 Acceptable ERA 4th/2020 11 /16/20 MRAD-33 Soil pCi/kQ Actinium-228 3530 3290 2170-4150 Acceptable ERA 4th/2020 11 /16/20 MRAD-33 Soil pCi/kg Americium-241 780 677 366 - 959 Acceptable ERA 4th/2020 11/16/20 MRAD-33 Soil PCi/kg Bismuth-212 3780 3290 942 -4900 Acceptable ERA 4th/2020 11 /16/20 MRAD-33 Soil PCi/ka Bismuth-214 2970 3790 1820 - 5640 Acceptable ERA 4th/2020 11/16/20 MRAD-33 Soil PCi/ka Cesium-1 34 3760 4180 2860 - 5000 Acceptable ERA 4th/2020 11 /16/20 MRAD-33 Soil pCi/ka Cesium-137 6890 6940 5250 - 8780 Acceptable

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PT Quarter I Analytical Sample GEL Known Acceptance Range/

Sample Number Unit Analyte I Nuclide Evaluation Provider Year Date Media Value value Ratio ERA 4th/2020 11 /16/20 MRAD-33 Soil pCi/kQ Cobalt-60 2280 2520 1980-3110 Acceptable ERA 4th/2020 11 /16/20 MRAD-33 Soil pCi/kg Lead-214 3680 4080 1710 - 6410 Acceptable ERA 4th/2020 11 /16/20 MRAD-33 Soil pCi/kQ Lead-214 3720 4080 1710-6410 Acceotable ERA 4th/2020 11 /16/20 MRAD-33 Soil oCi/ka Manganese-54 <23.9 <1000 <1000 Acceptable ERA 41h/2020 11 /16/20 MRAD-33 Soil pCi/kg Plutonium-238 1460 1670 833 - 2540 Acceptable ERA 4th/2020 11 /16/20 MRAD-33 Soil oCi/ka Potassium-40 24600 24700 17000 - 29500 Acceatable ERA 4th/2020 11 /16/20 MRAD-33 Soil oCi/ka Strontium-90 5110 4980 1550 - 7760 Acceotable ERA 4th/2020 11 /16/20 MRAD-33 Soil PCi/kg Thorium-234 5370 4740 1790-8120 Acceotable ERA 4th/2020 11 /16/20 MRAD-33 Soil pCi/ka Uranium-234 4550 4780 2240 - 6260 Acceotable ERA 4th/2020 11 /16/20 MRAD-33 Soil pCi/kQ Uranium-234 5100 4780 2240 - 6260 Acceptable ERA 4th/2020 11/16/20 MRAD-33 Soil pCi/kg Uranium-238 4800 4740 2600 - 6360 Acceptable ERA 4th/2020 11 /16/20 MRAD-33 Soil oCi/ka Uranium-238 4870 4740 2600 - 6360 Acceatable ERA 4th/2020 11 /16/20 MRAD-33 Soil oCi/ka Uranium-Total 9590 9730 5400 - 12600 Acceotable ERA 4th/2020 11/16/20 MRAD-33 Soil oCi/kg Uranium-Total 10189 9730 5400 - 12600 Acceotable ERA 4th/2020 11 /16/20 MRAD-33 Soil µg/kg Uranium-Total(mass) 14400 14200 6410- 19200 Acceptable ERA 4th/2020 11 /16/20 MRAD-33 Soil µg/kg Uranium-Total(mass) 14600 14200 6410 - 19200 Acceptable ERA 4th/2020 11 /16/20 MRAD-33 Soil pCi/kQ Zinc-65 1220 1120 895 - 1530 Acceptable ERA 4th/2020 11 /16/20 MRAD-33 Veaetation oCi/ka Americium-241 2680 2940 1820-4150 Acceptable ERA 4th/2020 11 /16/20 MRAD-33 Veaetation oCi/ka Cesium-134 862 945 627- 1260 Acceptable ERA 4th/2020 11 /16/20 MRAD-33 Veaetation oCi/ka Cesium-137 735 823 633- 1110 Acceotable ERA 4th/2020 11 /16/20 MRAD-33 Veaetation oCi/ka Cobalt-60 663 691 542 - 903 Acceotable ERA 4th/2020 11 /16/20 MRAD-33 Veaetation pCi/ka Curium-244 3100 3400 1920 - 4230 Acceotable ERA 4th/2020 11 /16/20 MRAD-33 Veaetation PCi/ka Manaanese-54 <47 .5 <300 <300 Acceotable ERA 4th/2020 11 /16/20 MRAD-33 Veaetation PCi/kg Plutonium-238 4470 4590 3180 - 5920 Acceotable ERA 4th/2020 11 /16/20 MRAD-33 Veaetation oCi/ka Plutonium-239 838 768 531 - 972 Acceotable ERA 4th/2020 11 /16/20 MRAD-33 VeQetation oCi/ka Potassium-40 33500 34500 25900 - 43700 Acceotable ERA 4th/2020 11 /16/20 MRAD-33 VeQetation oCi/kQ Strontium-90 8790 8690 4900 - 11300 Acceotable ERA 4th/2020 11 /16/20 MRAD-33 Veaetation oCi/kg Uranium-234 2650 2920 2050- 3720 Acceptable ERA 4th/2020 11 /16/20 MRAD-33 Vea eta ti on oCi/ka Uranium-238 2720 2900 2050 - 3630 Acceotable ERA 4th/2020 11 /16/20 MRAD-33 Veaetation oCi/ka Uranium-Total 5510 5950 3800 - 8020 Acceotable ERA 4th/2020 11 /16/20 MRAD-33 Vegetation µg/kg Uranium-Total(mass) 8150 8680 6660 - 10800 Acceptable ERA 4th/2020 11 /16/20 MRAD-33 Veaetation oCi/ka Zinc-65 1640 1580 1180 - 2340 Acceotable ERA 4th/2020 11 /16/20 MRAD-33 Air Filter oCi/Filter Americiu m-241 22.3 22.2 15.8 - 29 .6 Acceotable ERA 4th/2020 11 /16/20 MRAD-33 Air Filter oCi/Filter Cesium-134 268 296 192 - 363 Acceotable ERA 4th/2020 11 /16/20 MRAD-33 Air Filter oCi/Filter Cesium-137 407 413 339 - 542 Acceotable ERA 4th/2020 11 /16/20 MRAD-33 Air Filter oCi/Filter Cobalt-60 507 497 422 - 631 Acceotable ERA 4th/2020 11 /16/20 MRAD-33 Air Filter oCi/Filter lron-55 361 407 149 - 649 Acceotable ERA 4th/2020 11 /16/20 MRAD-33 Air Filter pCi/Filter Manganese-54 <3.82 <50.0 <50.0 Acceatable

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PT Quarter I Analytical Sample GEL Known Acceptance Range/ '

Sample Number Unit Analyte I Nuclide Evaluation Provider Year Date Media Value value Ratio ERA 4th/2020 11/16/20 MRAD-33 Air Filter pCi/Filter Plutonium-238 25.3 28.8 21.7 - 35.4 Acceptable ERA 4th/2020 11 /16/20 MRAD-33 Air Filter oCi/Filter Plutonium-239 31 33.7 25.2 - 40.7 Acceotable ERA 4th/2020 11 /16/20 MRAD-33 Air Filter pCi/Filter Strontium-90 30.5 36.2 22.9 - 49.3 Acceotable ERA 4th/2020 11 /16/20 MRAD-33 Air Filter oCi/Filter Uranium-234 16.5 18.3 13.6 - 21.4 Acceotable ERA 4th/2020 11 /16/20 MRAD-33 Air Filter oCi/Filter Uranium-234 19.5 18.3 13.6 - 21.4 Acceotable ERA 4th/2020 11 /16/20 MRAD-33 Air Filter pCi/Filter Uranium-238 18.5 18.1 13.7 - 21 .6 Acceptable ERA 4th/2020 11 /16/20 MRAD-33 Air Filter pCi/Filter Uranium-238 18.2 18.1 13.7 -21 .6 Acceotable ERA 4th/2020 11 /16/20 MRAD-33 Air Filter pCi/Filter Uranium-Total 35.8 37.2 27.2 -44.1 Acceotable ERA 4th/2020 11 /16/20 MRAD-33 Air Filter µg/Filter Uranium-Total(mass) 55.3 54.3 43.6 - 63.6 Acceptable ERA 4th/2020 11 /16/20 MRAD-33 Air Filter µg/Filter Uranium-Total( mass) 54.4 54.3 43.6 - 63.6 Acceptable ERA 4th/2020 11 /16/20 MRAD-33 Air Filter pCi/Filter Zinc-65 540 500 410 - 764 Acceptable ERA 4th/2020 11 /16/20 MRAD-33 Air Filter pCi/Filter Gross Alpha 32.2 26.1 13.6 - 43.0 Acceptable ERA 4th/2020 11 /16/20 MRAD-33 Air Filter pCi/Filter Gross Beta 94.2 85.9 52.1 - 130 Acceptable ERA 4th/2020 11 /16/20 MRAD-33 Water pCi/L Americium-241 185 176 121 - 225 Acceptable ERA 4th/2020 11 /16/20 MRAD-33 Water pCi/L Cesium-134 849 911 688 - 1000 Acceptable ERA 4th/2020 11 /16/20 MRAD-33 Water pCi/L Cesium-137 1540 1510 1290 - 1720 Acceptable ERA 4th/2020 11 /16/20 MRAD-33 Water pCi/L Cobalt-60 1660 1560 1350- 1790 Acceptable ERA 4th/2020 11/16/20 MRAD-33 Water pCi/L lron-55 267 298 175-433 Acceptable ERA 4th/2020 11 /16/20 MRAD-33 Water pCi/L Manganese-54 <4.61 <100 <100 Acceptable ERA 4th/2020 11/16/20 MRAD-33 Water pCi/L Plutonium-238 160 191 115 - 247 Acceptable ERA 4th/2020 11 /16/20 MRAD-33 Water pCi/L Plutonium-239 81 .7 100 61 .9 - 123 Acceptable ERA 4th/2020 11 /16/20 MRAD-33 Water pCi/L Strontium-90 917 787 567 - 973 Acceptable ERA 4th/2020 11/16/20 MRAD-33 Water pCi/L Uranium-234 33.8 35.2 26.8 -40.3 Acceptable ERA 4th/2020 11 /16/20 MRAD-33 Water pCi/L Uranium-234 39.2 35.2 26.8 - 40.3 Acceptable ERA 4th/2020 11/16/20 MRAD-33 Water pCi/L Uranium-238 34.7 34.9 27.0 -41 .1 Acceptable ERA 4th/2020 11 /16/20 MRAD-33 Water pCi/L Uranium-238 32.7 34.9 27.0 -41 .1 Acceptable ERA 4th/2020 11 /1 6/20 MRAD-33 Water oCi/L Uranium-238 37.3 34.9 27.0 -41 .1 Acceptable ERA 4th/2020 11/16/20 MRAD-33 Water oCi/L Uranium-Total 70.4 71 .8 56.0 - 81 .9 Acceptable ERA 4th/2020 11/16/20 MRAD-33 Water oCi/L Uranium-Total 78.2 71 .8 56.0 - 81 .9 Acceptable ERA 4th/2020 11/16/20 MRAD-33 Water µg/L Uranium-Total( mass) 104 105 85.0 - 119 Acceptable ERA 4th/2020 11/16/20 MRAD-33 Water µg/L Uranium-Total(mass) 112 105 85.0 - 119 Acceptable ERA 4th/2020 11/16/20 MRAD-33 Water pCi/L Zinc-65 1010 91 7 816 - 1160 Acceotable ERA 4th/2020 11/16/20 MRAD-33 Water pCi/L Gross Alpha 100 111 40. 5 -153 Acceotable ERA 4th/2020 11/16/20 MRAD-33 Water pCi/L Gross Beta 181 194 97.0 - 267 Acceotable ERA 4th/2020 11/16/20 MRAD-33 Water pCi/L Tritium 11600 12000 9040 - 14600 Acceptable MAPEP 4th/2020 12/14/20 MAPEP MaS43 Soil Bq/Kg Americium-241 1.2 False Pos Test Acceptable MAPEP 4th/2020 12/14/20 MAPEP MaS43 Soil Bq/Kg Cesium-134 625 710 497-923 Acceptable MAPEP 4th/2020 12/14/20 MAPEP MaS43 Soil Bq/Kg Cesium-137 0.87 False Pos Test Acceptable MAPEP 4th/2020 12/14/20 MAPEP MaS43 Soil Bq/Kg Cobalt-57 1260 1100 770-1430 Acceptable

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PT Quarter I Analytical Sample GEL Known Acceptance Range/

Sample Number Unit Analyte I Nuclide Evaluation Provider Year Date Media Value value Ratio MAPEP 4th/2020 12/14/20 MAPEP-20-MaS43 Soil Bq/Kg Cobalt-60 998 1000 700-1300 Acceptable MAPEP 4th/2020 12/14/20 MAPEP-20-MaS43 Soil Bq/Kg lron-55 811 577 404-750 Not Acceptable MA PEP 4th/2020 12/14/20 MAPEP MaS43 Soil Bq/Kg Manganese-54 661 610 427-793 Acceptable MAPEP 4th/2020 12/14/20 MAPEP MaS43 Soil Bq/Kg Nickel-63 840 980 686-1274 Acceptable MAPEP 4th/2020 12/14/20 MAPEP MaS43 Soil Bq/Kg Plutonium-238 53.1 57.7 40.4-75 Acceptable MAPEP 4th/2020 12/14/20 MAPEP MaS43 Soil Bq/Kg Plutonium-239/240 68.1 79.0 55-103 Acceptable MAPEP 4th/2020 12/14/20 MAPEP-20-MaS43 Soil Bq/Kg Potassium-40 704 622 435-809 Acceptable MA PEP 4th/2020 12/14/20 MAPEP-20-MaS43 Soil Bq/Kg Strontium-90 434 487 341-633 Acceptable MA PEP 4th/2020 12/14/20 MAPEP MaS43 Soil Bq/Kg Technetium-99 5 False Pos Test Acceptable MA PEP 4th/2020 12/14/20 MAPEP MaS43 Soil Bq/Kg U-234/233 51 48 33.7-62.5 Acceptable MA PEP 4th/2020 12/14/20 MAPEP MaS43 Soil Bq/Kg Uranium-238 126 128 90-166 Acceptable MAPEP 4th/2020 12/14/20 MAPEP MaS43 Soil Bq/Kg Zinc-65 531 470 329-611 Acceptable MAPEP 4th/2020 12/14/20 MAPEP-20-MaW43 Water Bq/L Americium-241 0.942 0.922 0.645-1.199 Acceptable MAPEP 4th/2020 12/14/20 MAPEP-20-MaW43 Water Bq/L Cesium-134 13.9 15.2 10.6-19.8 Acceptable MAPEP 4th/2020 12/14/20 MAPEP MaW43 Water Bq/L Cesium-137 15.10 14.3 10.0-18.6 Acceptable MAPEP 4th/2020 12/14/20 MAPEP MaW43 Water Bq/L Cobalt-57 -0.0072 False Pos Test Acceptable MAPEP 4th/2020 12/14/20 MAPEP MaW43 Water Bq/L Cobalt-60 12.90 12.2 8.5-15.9 Acceptable MA PEP 4th/2020 12/14/20 MAPEP MaW43 Water Bq/L Hydrogen-3 330 360 252-468 Acceptable MA PEP 4th/2020 12/14/20 MAPEP-20-MaW43 Water Bq/L lron-55 29.20 32.9 23.0-42.8 Acceptable MA PEP 4th/2020 12/14/20 MAPEP-20-MaW43 Water Bq/L Manganese-54 -0.0032 False Pos Test Acceptable MAPEP 4th/2020 12/14/20 MAPEP-20-MaW43 Water Bq/L Nickel-63 -0.93 False Pos Test Acceptable MAPEP 4th/2020 12/14/20 MAPEP MaW43 Water Bq/L Plutonium-238 0.6430 0.7040 0.493-0.915 Acceptable MAPEP 4th/2020 12/14/20 MAPEP MaW43 Water Bq/L Plutonium-239/240 0.001 0.009 Sens. Evaluation Acceptable MAPEP 4th/2020 12/14/20 MAPEP MaW43 Water Bq/L Potassium-40 -0.763 False Pos Test Acceptable MA PEP 4th/2020 12/14/20 MAPEP MaW43 Water Bq/L Radium-226 1.020 1.250 0.88-1.63 Acceptable MA PEP 4th/2020 12/14/20 MAPEP-20-MaW43 Water Bq/L Strontium-90 9.97 11.60 8.1-15.1 Acceptable MA PEP 4th/2020 12/14/20 MAPEP MaW43 Water Bq/L Technetium-99 8.720 9.40 6.6-12.2 Acceptable MA PEP 4th/2020 12/14/20 MAPEP-20-MaW43 Water Bq/L Uranium-234/233 1.27 1.26 0.88-1.64 Acceptable MAPEP 4th/2020 12/14/20 MAPEP-20-MaW43 Water Bq/L Uranium-238 1.31 1.30 0.9-1.7 Acceptable MAPEP 4th/2020 12/14/20 MAPEP MaW43 Water Bq/L Zinc-65 18.9 16.9 11.8-22 Acceptable MAPEP 4th/2020 12/14/20 MAPEP RdF43 Filter ug/sample Uranium-235 0.0920 0.1020 0.071-0.133 Acceptable MAPEP 4th/2020 12/14/20 MAPEP RdF43 Filter ug/sample Uranium-238 13.1 14.6 10.2-19 Acceptable MAPEP 4th/2020 12/14/20 MAPEP RdF43 Filter ug/sample Uranium-Total 13.2 14.7 10.3-19.1 Acceptable MA PEP 4th/2020 12/14/20 MAPEP-20-RdF43 Filter Bq/sample Americium-241 0.129 0.134 0.094-0.17 4 Acceptable MAPEP 4th/2020 12/14/20 MAPEP-20-RdF43 Filter Bq/sample Cesium-134 1.72 1.83 1.28-2.38 Acceptable MAPEP 4th/2020 12/14/20 MAPEP-20-RdF43 Filter Bq/sample Cesium-137 1.04 0.996 0.697-1.295 Acceptable MAPEP 4th/2020 12/14/20 MAPEP RdF43 Filter Bq/sample Cobalt-57 0.00126 False Pos Test Acceptable MAPEP 4th/2020 12/14/20 MAPEP RdF43 Filter Bq/sample Cobalt-60 1.85 1.73 1.21-2.25 Acceptable MAPEP 4th/2020 12/14/20 MAPEP RdF43 Filter Bq/sample Manganese-54 1.64 1.40 0.98-1.82 Acceptable MAPEP 4th/2020 12/14/20 MAPEP-20-RdF43 Filter Bq/sample Plutonium-238 0.0917 0.0867 0.0607-0.1127 Acceptable

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PT Quarter I Analytical Sample GEL Known Acceptance Range/

Sample Number Unit Analyte I Nuclide Evaluation Provider Year Date Media Value value Ratio MAPEP 4th/2020 12/14/20 MAPEP-20-RdF43 Filter Bq/sample Plutonium-239/240 0.0019 0.0017 Sens. Evaluation Acceptable MAPEP 4th/2020 12/14/20 MAPEP-20-RdF43 Filter Bq/sample Strontium-90 1.790 2.080 1.46-2.70 Acceptable MAPEP 4th/2020 12/14/20 MAPEP RdF43 Filter Bq/sample Uranium-234/233 0.1 820 0.175 0.123-0.228 Acceptable MAPEP 4th/2020 12/14/20 MAPEP RdF43 Filter Bq/sample Uranium-238 0.1860 0.182 0.1 27-0.237 Acceptable MAPEP 4th/2020 12/14/20 MAPEP RdF43 Filter Bq/sample Zinc-65 2.29 2.00 1.40-2.60 Acceptable MAPEP 4th/2020 12/14/20 MAPEP RdV43 Vegetation Bq/sample Americium-241 0. 1040 0.103 0.072-0.134 Acceptable MAPEP 4th/2020 12/14/20 MAPEP-20-RdV43 Vegetation Bq/sample Cesium-134 4.5 4.94 3.46-6.42 Acceptable MAPEP 4th/2020 12/14/20 MAPEP-20-RdV43 Vegetation Bq/sample Cesium-137 0.0134 False Pas Test Acceptable MAPEP 4th/2020 12/14/20 MAPEP RdV43 Vegetation Bq/sample Cobalt-57 6.70 6.67 4.67-8.67 Acceptable MAPEP 4th/2020 12/14/20 MAPEP RdV43 Vegetation Bq/sample Cobalt-60 4.27 4.13 2.89-5.37 Acceptable MAPEP 4th/2020 12/14/20 MAPEP RdV43 Vegetation Bq/sample Manganese-54 6.04 5.84 4.09-7.59 Acceptable MAPEP 4th/2020 12/14/20 MAPEP RdV43 Vegetation Bq/sample Plutonium-238 0.0002 0.001 Sens. Evaluation Acceptable MAPEP 4th/2020 12/14/20 MAPEP-20-RdV43 Vegetation Bq/sample Plutoniu m-239/240 0.05370 0.0624 0.0437-0.0811 Acceptable MAPEP 4th/2020 12/14/20 MAPEP-20-RdV43 Vegetation Bq/sample Strontium-90 1.07 1.39 0.97-1 .81 Acceptable MAPEP 4th/2020 12/14/20 MAPEP RdV43 Vegetation Bq/sample Uranium-234/233 0.1270 0.1150 0.081 -0.150 Acceptable MAPEP 4th/2020 12/14/20 MAPEP RdV43 Vegetation Bq/sample Uranium-238 0.1260 0.1200 0.084-0.156 Acceptable MAPEP 4th/2020 12/14/20 MAPEP RdV43 Vegetation Bq/sample Zinc-65 7.04 6.38 4.47-8.29 Acceptable EZA 4th/2020 2/1/2021 E13179 Cartridge pCi lodine-131 7.58E+01 7. 81E+01 0.97 Acceptable EZA 4th/2020 2/1/2021 E13180 Milk pCi/L Strontium-89 8.41E+01 8.97E+01 0.94 Acceptable EZA 4th/2020 2/1/2021 E13180 Milk pCi/L Strontium-90 1.13E+01 1.30E+01 0.87 Acceptable EZA 4th/2020 2/1/2021 E13181 Milk pCi/L Cerium-141 9.76E+01 1.00E+01 0.98 Acceptable EZA 4th/2020 2/1/2021 E13181 Milk pCi/L Cobalt-58 8.58E+01 8.43E+01 1.02 Acceptable EZA 4th/2020 2/1/2021 E13181 Milk pCi/L Cobalt-60 1.66E+02 1.52E+02 1.09 Acceptable EZA 4th/2020 2/1/2021 E13181 Milk pCi/L Chromium-51 2.68E+02 2.53E+02 1.06 Acceptable EZA 4th/2020 2/1/2021 E13181 Milk pCi/L Cesium-1 34 1.03E+02 1.08E+02 0.96 Acceptable EZA 4th/2020 2/1/2021 E13181 Milk pCi/L Cesium-137 1.33E+02 1.27E+02 1.04 Acceptable EZA 4th/2020 2/1/2021 E13181 Milk pCi/L lron-59 1.28E+02 1.12E+02 1.14 Acceptable EZA 4th/2020 2/1/2021 E13181 Milk pCi/L lodine-131 9.44E+0 1 9.19E+01 1.08 Acceptable EZA 4th/2020 2/1/2021 E13181 Milk pCi/L Manganese-54 1.49E+02 1.43E+02 1.04 Acceptable EZA 4th/2020 2/1/2021 E13181 Milk pCi/L Zinc-65 2.17E+02 1.90E+02 1.14 Acceptable EZA 4th/2020 2/1/2021 E13182 Water pCi/L Cerium-141 1.18E+02 1.06E+02 1.11 Acceptable EZA 4th/2020 2/1/2021 E13182 Water pCi/L Cobalt-58 9.54E+01 8.92E+01 1.07 Acceptable EZA 4th/2020 2/1/2021 E13182 Water pCi/L Cobalt-60 1.74E+02 1.61E+02 1.08 Acceptable EZA 4th/2020 2/1/2021 E13182 Water pCi/L Chromium-5 1 3.05E+02 2.68E+02 1.14 Acceptable EZA 4th/2020 2/1/2021 E13182 Water pCi/L Cesium-134 1.14E+02 1.14E+02 1.00 Acceptable EZA 4th/2020 2/1/2021 E13182 Water pCi/L Cesium-137 1.37E+02 1.35E+02 1.02 Acceptable EZA 4th/2020 2/1/2021 E13182 Water pCi/L lron-59 1.37E+02 1.19E+02 1.16 Acceptable EZA 4th/2020 2/1/2021 E13182 Water pCi/L lodine-131 9.72E+01 9.57E+01 1.02 Acceptable EZA 4th/2020 2/1/2021 E13182 Water pCi/L Manganese-54 1.65E+02 1.51E+02 1.09 Acceptable EZA 4th/2020 2/1/2021 E13182 Water pCi/L Zinc-65 2.29E+02 2.01E+02 1.14 Acceptable

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Table 6.1-2 2020 ECKERT & ZIEGLER ANALYTICS PERFORMANCE EVALUATION RESULTS Report Sample Sample GEL Acceptance Date Number Media Unit Analyte I Nuclide Value Known value Range/ Ratio Evaluation 05/08/20 E13167 Cartridge pCi lodine-131 9.37E+01 9.12E+01 1.03 Acceptable 05/08/20 E13168 Milk pCi/L Strontium-89 9.15E+01 9.55E+01 0.96 Acceptable 05/08/20 E13168 Milk pCi/L Strontium-90 1.51E+02 1.43E+02 0.62 Acceptable 05/08/20 E13169 Milk pCi/L Cerium-141 1.99E+02 1.84E+02 1.08 Acceptable 05/08/20 E13169 Milk pCi/L Cobalt-58 1.96E+02 1.89E+02 1.03 Acceptable 05/08/20 E13169 Milk pCi/L Cobalt-60 2.33E+02 2.29E+02 1.02 Acceptable 05/08/20 E13169 Milk pCi/L Chromium-51 3.84E+02 3.76E+02 1.02 Acceptable 05/08/20 E13169 Milk pCi/L Cesium-134 1.36E+02 1.49E+02 0.91 Acceptable 05/08/20 E13169 Milk pCi/L Cesium-137 1.91 E+02 1.80E+02 1.06 Acceptable 05/08/20 E13169 Milk pCi/L Manganese-54 2.31 E+02 2.10E+02 1.1 Acceptable 05/08/20 E13169 Milk pCi/L lron-59 1.82E+02 1.63E+02 1.12 Acceptable 05/08/20 E13169 Milk pCi/L Zinc-65 2.69E+02 2.52E+02 1.07 Acceptable 05/08/20 E13170 Water pCi/L Cerium-141 2.11E+02 1.90E+02 1.11 Acceptable 05/08/20 E13170 Water pCi/L Cesium-134 1.53E+02 1.54E+02 0.99 Acceptable 05/08/20 E13170 Water pCi/L Cesium-137 2.08E+02 1.85E+02 1.12 Acceptable 05/08/20 E13170 Water pCi/L Chromium-51 4.34E+02 3.88E+02 1.12 Acceptable 05/08/20 E13170 Water pCi/L Cobalt-58 2.21E+02 1.96E+02 1.13 Acceptable 05/08/20 E13170 Water pCi/L Cobalt-60 2.59E+02 2.36E+02 1.10 Acceptable 05/08/20 E13170 Water pCi/L lodine-131 1.02E+02 9.29E+01 1.1 Acceptable 05/08/20 E13170 Water pCi/L lron-59 1.79E+02 1.68E+02 1.06 Acceptable 05/08/20 E13170 Water pCi/L Manganese-54 2.48E+02 2.16E+02 1.15 Acceptable 05/08/20 E13170 Water pCi/L Zinc-65 3.05E+02 2.61E+02 1.17 Acceptable 07/31/20 E13171 Cartridge pCi lodine-131 9.68E+01 9.19E+01 1.05 Acceptable 07/31/20 E13172 Milk pCi/l Strontium-89 8.67E+01 8.81 E+01 0.98 Acceptable 07/31/20 E13172 Milk pCi/L Strontium-90 1.06E+01 1.27E+01 0.83 Acceptable 07/31/20 E13173 Milk pCi/L Cerium-141 1.29E+02 1.16E+02 1.11 Acceptable 07/31/20 E13173 Milk pCi/L Cobalt-58 1.04E+02 1.00E+02 1.03 Acceptable 07/31/20 E13173 Milk pCi/L Cobalt-60 2.00E+02 1.95E+02 1.02 Acceptable 07/31/20 E13173 Milk pCi/L Chromium-51 2.91E+02 2.56E+02 1.14 Acceptable 07/31/20 E13173 Milk pCi/L Cesium-134 1.40E+02 1.46E+02 0.96 Acceptable

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Report Sample Sample GEL Acceptance Date Number Media Unit Analvte I Nuclide Value Known value Range/ Ratio Evaluation 07/31/20 E13173 Milk pCi/L Cesium-137 1.09E+02 1.04E+02 1.05 Acceptable 07/31/20 E131 73 Milk pCi/L lron-59 1.09E+02 1.01 E+02 1.08 Acceptable 07/31/20 E13173 Milk pCi/L lodine-131 8.31 E+01 8.15E+01 1.02 Acceptable 07/31/20 E1 3173 Milk pCi/L Manganese-54 1.41E+02 1.34E+02 1.05 Acceptable 07/31/20 E1 3173 Milk pCi/L Zinc-65 2.48E+02 2.25E+02 1.10 Acceptable 07/31/20 E13174 Water pCi/L Cerium-141 1.23E+02 1.17E+02 1.05 Acceptable 07/31/20 E13174 Water pCi/L Cobalt-58 1.05E+02 1.02E+02 1.03 Acceptable 07/31/20 E1 3174 Water pCi/L Cobalt-60 2.05E+02 1.98E+02 1.04 Acceptable 07/31/20 E1 3174 Water pCi/L Chromium-51 2.76E+02 2.59E+02 1.06 Acceptable 07/31 /20 E13174 W ater pCi/L Cesiutn-134 1.36E+02 1.48E+02 0.92 Acceptable 07/31/20 E13174 Water pCi/L Cesium-137 1.04E+02 1.05E+02 0.99 Acceptable 07/31/20 E13174 Water pCi/L lron-59 1.05E+02 1.02E+02 1.03 Acceptable 07/31/20 E1 3174 Water pCi/L lodine-131 9.10E+01 8.05E+01 1.13 Acceptable 07/31/20 E131 74 Water pCi/L Manganese-54 1.47E+02 1.35E+02 1.09 Acceptable 07/31 /20 E13174 Water pCi/L Zinc-65 2.49E+02 2.27E+02 1.10 Acceptable 11 /1 0/20 E13175 Cartridge pCi lodine-131 7.96E+01 7.67E+01 1.04 Acceptable 11 /1 0/20 E13176 Milk pCi/L Strontium-89 1.13E+02 9.54E+01 1.18 Acceptable 11/10/20 E1 3176 Milk pCi/L Strontium-90 9.47E+01 1.28E+02 0.74 Acceptable 11/10/20 E1 3177 Milk pCi/L Cerium-141 1.47E+02 1.50E+02 0.98 Acceptable 11/10/20 E1 3177 Milk pCi/L Cobalt-58 1.81 E+02 1.80E+02 1.01 Acceptable 11/10/20 E1 3177 Milk pCi/L Cobalt-60 3.85E+02 3.79E+02 1.02 Acceptable 11/10/20 E1 3177 Milk pCi/L Chromium-51 4.11E+02 3.72E+02 1.10 Acceptable 11 /10/20 E1 3177 Milk pCi/L Cesium-1 34 1.82E+02 2.00E+02 0.91 Acceptable 11 /10/20 E13177 Milk pCi/L Cesium-1 37 2.58E+02 2.50E+02 1.03 Acceptable 11/10/20 E1 3177 Milk pCi/L lron-59 2.29E+02 2.00E+02 1.14 Acceptable 11/10/20 E13177 Milk pCi/L lodine-1 31 9.49E+01 9.50E+01 1.00 Acceptable 11/10/20 E131 77 Milk pCi/L Manganese-54 1.96E+02 1.80E+02 1.09 Acceptable 11 /1 0/20 E13177 Milk pCi/L Zinc-65 3.04E+02 2.70E+02 1.13 Acceptable 11 /1 0/20 E13178 Water pCi/L Cerium-141 1.58E+02 1.51 E+02 1.05 Acceptable 11 /10/20 E13178 Water pCi/L Cobalt-58 1.90E+02 1.80E+02 1.05 Acceptable 11 /1 0/20 E13178 Water pCi/L Cobalt-60 4.04E+02 3.80E+02 1.06 Acceptable 11/10/20 E13178 Water pCi/L Chromium-51 3.45E+02 3.73E+02 0.92 Acceptable 11/10/20 E13178 Water pCi/L Cesium-1 34 1.81 E+02 2.01E+02 0.9 Acceptable 11/1 0/20 E13178 W ater pCi/L Cesium-137 2.63E+02 2.51E+02 1.05 Acceptable 11/1 0/20 E13178 Water pCi/L lron-59 2.26E+02 2.01E+02 1.1 2 Acceptable 11/10/20 E1 3178 Water pCi/L lodine-1 31 9.80E+01 9.82E+01 1.00 Acceptable

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Report Sample Sample GEL Acceptance Date Number Media Unit Analvte I Nuclide Value Known value Ranae/ Ratio Evaluation 11 /10/20 E13178 Water pCi/L Manganese-54 2.06E+02 1.81E+02 1.14 Acceptable 11 /10/20 E13178 Water pCi/L Zinc-65 3.02E+02 2.71E+02 1.12 Acceptable 2/1/2021 E13179 Cartridge pCi lodine-131 7.58E+01 7.81E+01 0.97 Acceptable 2/1/2021 E13180 Milk pCi/L Strontium-89 8.41 E+01 8.97E+01 0.94 Acceptable 2/1/2021 E13180 Milk pCi/L Strontium-90 1.13E+01 1.30E+01 0.87 Acceptable 2/1/2021 E13181 Milk pCi/L Cerium-141 9.76E+01 1.00E+01 0.98 Acceptable 2/1/2021 E13181 Milk pCi/L Cobalt-58 8.58E+01 8.43E+01 1.02 Acceptable 2/1/2021 E13181 Milk pCi/L Cobalt-60 1.66E+02 1.52E+02 1.09 Acceptable 2/1/2021 E13181 Milk pCi/L Chromium-51 2.68E+02 2.53E+02 1.06 Acceptable 2/1/2021 E13181 Milk pCi/L Cesium-134 1.03E+02 1.08E+02 0.96 Acceptable 2/1/2021 E13181 Milk pCi/L Cesium-137 1.33E+02 1.27E+02 1.04 Acceptable 2/1/2021 E13181 Milk pCi/L lron-59 1.28E+02 1.12E+02 1.14 Acceptable 2/1/2021 E13181 Milk pCi/L lodine-131 9.44E+01 9.19E+01 1.08 Acceptable 2/1/2021 E13181 Milk pCi/L Manganese-54 1.49E+02 1.43E+02 1.04 Acceptable 2/1/2021 E13181 Milk pCi/L Zinc-65 2.17E+02 1.90E+02 1.14 Acceptable 2/1/2021 E13182 Water pCi/L Cerium-141 1.18E+02 1.06E+02 1.11 Acceptable 2/1/2021 E13182 Water pCi/L Cobalt-58 9.54E+01 8.92E+01 1.07 Acceptable 2/1/2021 E13182 Water pCi/L Cobalt-60 1.74E+02 1.61E+02 1.08 Acceptable 2/1/2021 E13182 Water pCi/L Chromium-51 3.05E+02 2.68E+02 1.14 Acceptable 2/1/2021 E13182 Water pCi/L Cesium-134 1.14E+02 1.14E+02 1.00 Acceptable 2/1/2021 E13182 Water pCi/L Cesium-137 1.37E+02 1.35E+02 1.02 Acceptable 2/1/2021 E13182 Water pCi/L lron-59 1.37E+02 1.19E+02 1.16 . Acceptable 2/1/2021 E13182 Water pCi/L lodine-131 9.72E+01 9.57E+01 1.02 Acceptable 2/1/2021 E13182 Water pCi/L Manganese-54 1.65E+02 1.51 E+02 1.09 Acceptable 2/1/2021 E13182 Water pCi/L Zinc-65 2.29E+02 2.01 E+02 1.14 Acceptable

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TABLE 6.1-3 REMP INTRA-LABORATORY DATA

SUMMARY

BIAS AND PRECISION BY MATRIX Bias Criteria Precision Criteria C+ I - 250/ol CNote 1)

WITHIN OUTSIDE WITHIN OUTSIDE REMP 2020 CRITERIA CRITERIA CRITERIA CRITERIA MILK Gas Flow Sr 2nd count 46 0 57 0 Gas Flow Total Strontium 16 0 16 0 Gamma Spec Liquid RAD A-013 with Ba, La 28 0 82 0 Gamma Spec Liquid RAD A-013 with Iodine 0 0 3 0 SOLID Gamma Spec Solid RAD A-013 9 0 12 0 LSC Nickel 63 4 0 4 0 Gas Flow Sr 2nd count 4 0 7 0 Gas Flow Total Strontium 3 0 4 0 Gamma Spec Solid RAD A-013 with Iodine 22 0 48 0 FILTER Gross A & B 512 0 362 0 Gamma Spec Filter 43 0 83 0 LIOUID Alpha Spec Uranium 1 0 1 0 Tritium 212 0 271 0 LSC lron-55 17 0 15 0 LSC Nickel 63 17 0 15 0 Gamma lodine-131 6 0 7 0 Alpha Spec Plutonium 1 0 1 0 Gas Flow Sr 2nd count 2 0 3 0 Alpha Spec Am241 Curium 1 0 1 0 Gas Flow Total Strontium 16 0 14 0 Gross Alpha Non Vol Beta 33 0 71 0 Gamma Spec Liquid RAD A-013 with Ba, La 76 0 191 0 Gamma Spec Liauid RAD A-013 with Iodine 25 0 80 0 TISSUE Gamma Spec Solid RAD A-013 40 0 49 0 Gas Flow Sr 2nd count 12 0 10 0 Gas Flow Total Strontium 8 0 7 0 Gamma Spec Solid RAD A-013 with Iodine 21 0 21 0 VEGETATION Gamma Spec Solid RAD A-013 13 0 13 0 Gas Flow Sr 2nd count 10 0 11 0 Gamma Spec Solid RAD A-013 with Iodine 83 0 110 0 AIR CHARCOAL Carbon-14 (Ascarite/Soda Lime Filter per Liter) 35 0 35 0 133

Bias Criteria Precision Criteria C+ I - 250/ol (Note ll WITHIN OUTSIDE WITHIN OUTSIDE REMP 2020 CRITERIA CRITERIA CRITERIA CRITERIA DRINKING WATER Tritium 36 0 39 0 LSC lron-55 14 0 16 0 LSC Nickel 63 14 0 16 0 Gamma lodine-131 31 0 22 0 Gas Flow Sr 2nd count 15 0 14 0 Gas Flow Total Strontium 13 0 15 0 Gross Alpha Non Vol Beta 77 0 82 0 Gamma Spec Liquid RAD A-013 with Ba, La 21 0 73 0 Gamma Spec Liquid RAD A-013 with Iodine 0 0 6 0 Total 1537 1887 Note 1: The RPO must be 20 percent or less, if both samples are greater than 5 times the MDC. If both results are less than 5 times MDC, then the RPO must be equal to or less than 100%. If one result is above the MDC and the other is below the MDC, then the RPO can be calculated using the MDC for the result of the one below the MDC. The RPO must be 100% or less. In the situation where both results are above the MDC but one result is greater than 5 times the MDC and the other is less than 5 times the MDC, the RPO must be less than or equal to 20%. If both results are below MDC, then the limits on % RPO are not aoolicable.

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Table 6.1-4 ALL RADIOLOGICAL INTRA-LABORATORY DATA

SUMMARY

BIAS AND PRECISION BY MATRIX Bias Criteria ( + I - 25% Precision Criteria (Note 1 l WITHIN OUTSIDE WITHIN OUTSIDE Total Radioloaical 2020 CRITERIA CRITERIA CRITERIA CRITERIA MILK Gamma Spec Liquid RAD A-013 5 0 5 0 Gamma lodine-129 6 0 6 0 Gamma lodine-131 5 0 116 0 Gas Flow Sr 2nd count 46 0 57 0 Gas Flow Strontium 90 10 0 11 0 Gas Flow Total Strontium 16 0 16 0 Gamma Spec Liauid RAD A-013 with Ba, La 28 0 82 0 Gamma Spec Liquid RAD A-013 with Iodine 5 0 7 0 SOLID Gas Flow Radium 228 71 0 75 0 Alpha Spec Neptunium 471 0 455 0 Tritium 345 0 406 0 Tritium by Pyrolysis 0 0 1 0 Carbon-14 232 0 283 0 Carbon-14 bv Pvrolvsis 0 0 1 0 LSC lron-55 135 0 146 0 Alpha Spec Polonium Solid 37 0 52 0 Gamma Nickel 59 RAD A-022 140 0 156 0 LSC Chlorine-36 in Solids 1 0 2 0 Gamma Spec Ra226 RAD A-013 22 0 25 0 Gamma Soec Solid RAD A-013 1122 0 1398 0 LSC Nickel 63 201 0 215 0 LSC Plutonium 219 0 234 0 Technetium-99 543 0 564 0 Gamma Spec Liquid RAD A-013 1 0 1 0 Gross Aloha Beta Soil Leach 31 0 31 0 ICP-MS Technetium-99 in Soil 6 0 3 0 LSC Selenium 79 15 0 19 0 Total Activitv, 8 0 13 0 Tritium 26 0 27 0 Alpha Spec Am243 89 0 108 0 Gamma lodine-129 93 0 160 0 Gas Flow Lead 210 19 0 23 0 Alpha Soec Uranium 746 0 900 0 LSC Promethium 147 1 0 4 0 LSC, Rapid Strontium 89 and 90 67 0 74 0 Alpha Spec Thorium 470 0 567 0

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Bias Criteria <+ I - 250/o Precision Criteria (Note 1)

WITHIN OUTSIDE WITHIN OUTSIDE Total Radioloaical 2020 CRITERIA CRITERIA CRITERIA CRITERIA ICP-MS Uranium-233, 234 in Solid 55 0 57 0 LSC Sulfur 35 2 0 3 0 Alpha Spec Neptunium (oCi/Samole) 3 0 3 0 Alpha Spec Plutonium 509 0 486 0 ICP-MS Technetium-99 Prep in Soil 6 0 3 0 LSC Calcium 45 0 0 1 0 Alpha Spec Plutonium 158 0 232 0 Alpha Spec Radium 226 34 0 45 0 Dissolution Soil Preo 4 0 4 0 Gas Flow Sr 2nd count 27 0 35 0 Gas Flow Strontium 90 335 0 308 0 Gas Flow Total Radium 2 0 2 0 Lucas Cell Radium 226 98 0 116 0 Alpha Spec Am241 Curium 438 0 483 0 Alpha Spec Total Uranium 62 0 64 0 Gas Flow Total Strontium 51 0 53 0 ICP-MS Uranium-233, 234 Prep in Solid 57 0 59 0 ICP-MS Uranium-235, 236, 238 in Solid 57 0 65 0 Alpha Spec Polonium Solid 3 0 3 0 Gamma Spec Solid RAD A-013 with Iodine 22 0 48 0 GFC Chlorine-36 in Solids 13 0 19 0 Gamma Spec Solid RAD A-013 (oCi/Samole) 6 0 5 0 Technetium-99 3 0 3 0 Tritium 1 0 3 0 Alpha Spec Am241 (pCi/Sample) 3 0 3 0 ICP-MS Uranium-234, 235, 236, 238 in Solid 223 0 264 0 ICP-MS Uranium-235, 236, 238 Prep in Solid 65 0 81 0 Alpha Spec Thorium 2 0 3 0 Gross Aloha/Beta (Am/Cs Calibration) Solid 0 0 2 0 ICP-MS U-234, 235, 236, 238 Preo oer samole 13 0 13 0 Gross Aloha/Beta 403 0 502 0 Alpha Spec Plutonium 3 0 3 0 Gas Flow Strontium 90 3 0 3 0 Gross Alpha/Beta (Americium Calibration) Solid 1 0 1 0 ICP-MS Uranium-234, 235, 236, 238 Prep in Solid 93 0 149 0 Gross Aloha Beta (F,U) 30 0 33 0 FILTER Alpha Spec Polonium 0 0 8 0 Gamma 1-131, filter 5 0 5 0

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Bias Criteria l + I - 250/o Precision Criteria (Note 1)

WITHIN OUTSIDE WITHIN OUTSIDE Total Radioloaical 2020 CRITERIA CRITERIA CRITERIA CRITERIA Alpha Spec Neptunium 69 0 109 0 LSC Plutonium Filter 74 0 129 0 Tritium 34 0 242 0 Carbon-14 Direct Count 0 0 54 0 Carbon-14 1 0 97 0 ICP-MS Tc-99 in Filter 0 0 5 0 Nickel-63 0 0 25 0 LSC lron-55 76 0 94 0 Gamma Nickel 59 RAD A-022 84 0 110 0 Alpha Spec Californium FPL 12 0 12 0 LSC Nickel 63 71 0 98 0 Technetium-99 7 0 103 0 Gamma Spec Filter RAD A-013 158 0 246 0 ICP-MS Tc-99 Prep in Filter 0 0 9 0 Alphaspec Np Filter per Liter 19 0 24 0 Alphaspec Pu Filter per Liter 19 0 33 0 Gamma lodine-129 1 0 79 0 Alpha Spec Am243 17 0 38 0 Gas Flow Lead 210 1 0 6 0 Alpha Spec Uranium 49 0 118 0 LSC Promethium 147 0 0 1 0 LSC , Rapid Strontium 89 and 90 89 0 107 0 Alpha Spec Thorium 34 0 91 0 Gas Flow Radium 228 2 0 16 0 Alpha Spec Plutonium 48 0 121 0 ICP-MS Uranium-233, 234 in Filter 1 0 10 0 LSC Sulfur 35 0 0 1 0 Alpha Spec Plutonium 96 0 176 0 Alpha Spec Plutonium 11 0 11 0 Alpha Spec Polonium,(Filter/Liter) 0 0 2 0 Alpha Spec Radium 226 0 0 13 0 Gas Flow Sr 2nd Count 34 0 60 0 Gas Flow Strontium 90 57 0 101 0 Gas Flow Total Radium 1 0 5 0 LSC Plutonium 241 Filter per Liter 20 0 45 0 Lucas Cell Radium-226 0 0 12 0 Alpha Spec Am241 Curium 101 0 181 0 ICP-MS Uranium-233, 234 Prep in Filter 1 0 9 0 ICP-MS Uranium-235, 236, 238 in Filter 4 0 13 0 Total Activity in Filter, 0 0 51 0

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Bias Criteria ( + I - 250/o Precision Criteria (Note 1 l WITHIN OUTSIDE WITHIN OUTSIDE Total Radioloaical 2020 CRITERIA CRITERIA CRITERIA CRITERIA Alphaspec Am241 Curium Filter per Liter 33 0 76 0 Tritium 96 0 130 0 GFC Chlorine-36 in Filters 0 0 1 0 Gamma Spec Filter RAD A-013 Direct Count 3 0 9 0 Carbon-14 22 0 35 0 GFC Chlorine-36 in Filters PL 1 0 1 0 Gross A & B (Americium Calibration) Liquid 1 0 42 0 Direct Count-Gross Aloha/Beta 89 0 0 0 Gross Aloha/Beta 41 0 57 0 ICP-MS Uranium-234, 235, 236, 238 in Filter 7 0 55 0 ICP-MS Uranium-235, 236, 238 Preo in Filter 4 0 12 0 Aloha Spec U 33 0 77 0 Gross A & B 568 0 443 0 LSC lron-55 8 0 17 0 Technetium-99 29 0 49 0 Gas Flow Sr-90 19 0 45 0 LSC Nickel 63 37 0 45 0 Gamma Spec Charcoal 11 0 11 0 Gas Flow Pb-210 13 0 34 0 Gas Flow Ra-228 13 0 28 0 Gross Alpha Beta (Flame, Unflame) 10 0 10 0 Direct Count- Alpha/Beta (Americium Calibration) 21 0 0 0 Gamma Iodine 129 8 0 8 0 ICP-MS Uranium-234, 235, 236, 238 Prep in Filter 3 0 27 0 Gamma Soec Filter 99 0 154 0 Lucas Cell Ra-226 8 0 38 0 Alpha Spec Thorium 23 0 47 0 LIQUID Alpha Spec Uranium 496 0 756 0 Aloha Soec Polonium 19 0 20 0 Alpha Spec Neptunium 172 0 236 0 Tritium 1276 0 1383 0 Carbon-14 186 0 219 0 Plutonium 131 0 151 0 Chlorine-36 in Liauids 4 0 5 0 lodine-131 6 0 4 0 LSC lron-55 100 0 167 0 Gamma Nickel 59 RAD A-022 27 0 43 0 Gamma Iodine 131 RAD A-013 2 0 2 0

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Bias Criteria ( + I - 25% Precision Criteria <Note 1 l WITHIN OUTSIDE WITHIN OUTSIDE Total Radioloaical 2020 CRITERIA CRITERIA CRITERIA CRITERIA LSC Nickel 63 144 0 197 0 LSC Radon 222 18 0 22 0 Technetium-99 673 0 720 0 Gamma Spec Liauid RAD A-013 859 0 970 0 Alpha Spec Total U RAD A-011 24 0 40 0 LSC Selenium 79 38 0 38 0 Total Activity, 15 0 20 0 Alpha Spec Am243 20 0 26 0 Gamma lodine-129 145 0 182 0 Gamma lodine-131 6 0 7 0 ICP-MS Technetium-99 in Water 8 0 9 0 Gas Flow Lead 210 11 0 16 0 Gross Alpha, Beta 5 0 5 0 LSC Promethium 147 22 0 22 0 LSC, Rapid Strontium 89 and 90 9 0 15 0 Alpha Spec Thorium 237 0 316 0 Gas Flow Radium 228 14 0 7 0 Gas Flow Radium 228 682 0 728 0 Alpha Spec Plutonium 354 0 482 0 LSC Sulfur 35 17 0 17 0 Alpha Spec Plutonium 41 0 51 0 Alpha Spec Radium 226 32 0 37 0 Gas Flow Sr 2nd count 102 0 161 0 Gas Flow Strontium 90 511 0 584 0 Gas Flow Strontium 90 5 0 5 0 Gas Flow Total Radium 428 0 328 0 ICP-MS Technetium-99 Prep in Water 8 0 9 0 ICP-MS Uranium-233, 234 in Liauid 7 0 11 0 LSC Calcium 45 15 0 15 0 Lucas Cell Radium 226 372 0 597 0 Lucas Cell Radium-226 12 0 13 0 Chlorine-36 in Liauids 19 0 21 0 Alpha Spec Am241 Curium 317 0 427 0 Gas Flow Total Strontium 100 ,0 103 0 Gross Aloha Non Vol Beta 868 0 1213 0 LSC Phosphorus-32 4 0 4 0 ICP-MS Uranium-233, 234 Prep in Liauid 5 0 9 0 Tritium in Drinking Water by EPA 906.0 5 0 5 0 Gamma Spec Liquid RAD A-013 with Ba, La 78 0 203 0 Gamma Spec Liquid RAD A-013 with Iodine 97 0 174 0 Gas Flow Strontium 89 & 90 2 0 3 0

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Bias Criteria ( + I - 25% Precision Criteria {Note 1)

WITHIN OUTSIDE WITHIN OUTSIDE Total Radioloaical 2020 CRITERIA CRITERIA CRITERIA CRITERIA ICP-MS Uranium-235, 236, 238 in Liquid 11 0 13 0 Gas Flow Total Alpha Radium 15 0 15 0 Gross Alpha Co-precipitation 3 0 28 0 ICP-MS Uranium-235, 236, 238 Prep in Liquid 7 0 11 0 Gross Alpha/Beta 0 0 1 0 ICP-MS Uranium-234, 235, 236, 238 in Liquid 147 0 132 0 Gross Alpha Beta (Flame, Unflame) 284 0 303 0 Gross Alpha Beta (Americium Calibration) Liquid 47 0 95 0 ICP-MS Uranium-234, 235, 236, 238 Prep in Liquid 69 0 66 0 Alpha/Beta (Americium Calibration) Drinking Water 38 0 37 0 TISSUE Gamma Spec Solid RAD A-013 48 0 63 0 Alpha Spec Uranium 5 0 6 0 Alpha Soec Plutonium 5 0 5 0 Gas Flow Sr 2nd count 12 0 10 0 Gas Flow Strontium 90 7 0 6 0 Alpha Spec Am241 Curium 3 0 3 0 Gas Flow Total Strontium 8 0 7 0 Gamma Soec Solid RAD A-013 with Iodine 21 0 21 0 Gross Alpha/Beta 3 0 3 0 VEGETATION Carbon-14 3 0 2 0 Gamma Soec Solid RAD A-013 39 0 36 0 Tritium 2 0 1 0 Gas Flow Lead 210 0 0 5 0 Alpha Spec Uranium 25 0 21 0 Alpha Spec Thorium 10 0 10 0 Alpha Spec Plutonium 24 0 17 0 Gas Flow Sr 2nd count 10 0 11 0 Gas Flow Strontium 90 21 0 14 0 Gas Flow Total Radium 3 0 5 0 Alpha Spec Am241 Curium 6 0 5 0 Gamma Spec Solid RAD A-013 with Iodine 83 0 110 0 Gamma Spec Solid RAD A-013 (pCi/Sample) 3 0 3 0 Alpha Spec Am241 (pCi/Samole) 3 0 3 0 Alpha Spec Uranium 0 0 3 0 Gross Aloha/Beta 5 0 8 0 Alpha Spec Plutonium 0 0 3 0

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Bias Criteria ( + I - 250/o Precision Criteria (Note 1)

WITHIN OUTSIDE WITHIN OUTSIDE Total Radioloaical 2020 CRITERIA CRITERIA CRITERIA CRITERIA Gas Flow Strontium 90 6 0 3 0

, AIR CHARCOAL Gamma lodine-129 19 0 8 0 Carbon-14 15 0 15 0 Carbon-14 (Ascarite/Soda Lime Filter per Liter) 35 0 35 0 Gamma Spec Charcoal 15 0 15 0 Gamma Iodine 129 15 0 15 0 DRINKING WATER Alpha Spec Uranium 2 0 1 0 Tritium 38 0 41 0 LSC lron-55 14 0 16 0 LSC Nickel 63 14 0 16 0 LSC Radon 222 9 0 10 0 Gamma Spec Liauid RAD A-013 4 0 4 0 Gamma lodine-129 3 0 5 0 Gamma lodine-131 31 0 22 0 Gas Flow Lead 210 1 0 1 0 Gas Flow Radium 228 43 0 46 0 Gas Flow Radium 228 0 0 3 0 Gas Flow Sr 2nd count 15 0 14 0 Gas Flow Strontium 90 12 0 13 0 Gas Flow Total Radium 2 0 1 0 Lucas Cell Radium 226 3 0 3 0 Lucas Cell Radium-226 48 0 46 0 Gamma Spec Drinking Water RAD A-013 35 0 28 0 Gas Flow Total Strontium 13 0 15 0 Gross Alpha Non Vol Beta 175 0 188 0 Tritium in Drinkina Water bv EPA 906.0 44 0 44 0 Gamma Spec Liquid RAD A-013 with Ba, La 21 0 73 0 Gamma Spec Liquid RAD A-013 with Iodine 0 0 6 0 Gas Flow Strontium 89 & 90 18 0 4 0 Alpha/Beta (Americium Calibration) Drinking Water 13 0 11 0 ECLS-R-GA NJ 48 Hr Rapid Gross Alpha 5 0 5 0 Tota' 20799 26108 Note 1: The RPO must be 20 percent or less, if both samples are greater than 5 times the MDC. If both results are less than 5 times MDC, then the RPO must be equal to or less than 100%. If one result is above the MDC and the other is below the MDC, then the RPO can be calculated using the MDC for the result of the one below the MDC. The RPO must be 100% or less. In the situation where both results are above the MDC but one result is greater than 5 times the MDC and the other is less than 5 times the MDC, the RPO must be less than or equal to 20%. If both results are below MDC, then the limits on % RPO are not applicable.

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Table 6.1-5 2020 CORRECTIVE ACTION REPORT

SUMMARY

CORRECTIVE ACTION ID#

& DISPOSITION PE FAILURE CARR 201214-1296 Root Cause Analysis ISO Documentation of PT Failure in Upon receipt of the PT report, an investigation was initiated by the MAPEP 43 for: Quality Department and a Corrective Action (CARR) team assembled. The team consisted of representatives from the

Fe-55 in soil affected areas. The sample preparation and analytical processes were reviewed. This included review of reagents and standards used in the sample preparation steps, calibration records, process control samples, and interviews with the analysts.

The investigation determined that the laboratory met all quality control criteria specified in the method. Additionally, all internal procedures and policies were performed as required. These failures were tracked through GEL's internal non-conformance system.

lron-55:

The laboratory reviewed the data and noted that the tracer recoveries for this analysis were lower than typical soil tracer recoveries. The lower tracer recoveries contributed to an uncertainty of approximately 25%.

The sample was recounted and recovered at 97% of the known value.

Permanent Corrective/Preventive Actions or Improvements None at this time. The laboratory will continue to monitor the recoveries of these parameters to ensure that there are no continued issues in the processes.

CARR 200902-1287 Root Cause Analysis ISO Documentation of PT Failure in The data was reviewed and no anomalies were noted. The batch RAD-122 in drinking water for: duplicate result from the original analysis met the acceptance criteria of the study and replication criteria of the laboratory with

Ba-133 RPDs of <10% for both isotopes. Laboratory processes were

Co-60 evaluated and no gross errors were found. The other reported analytes for this method were within the limits of the study. A definitive contributor to the slightly high bias could not be identified concluding that this was an isolated occurrence for these isotopes.

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CORRECTIVE ACTION ID#

& DISPOSITION PE FAILURE Permanent Corrective/Preventive Actions or Improvements None at this time. The laboratory will continue to monitor the recoveries of these parameters to ensure that there are no continued issues in the processes.

CARR 200902-1278 Root Cause Analysis ISO Documentation of PT Failure in Filter: The sample was analyzed at 20X. As part of the MRAD - 32 for: investigation, the sample was reanalyzed at 5X and the results were within acceptance limits.

U-238 filter

Total U (mass) filter Water: The samples were reanalyzed, and the results were within the acceptance limits. In reviewing the data, the laboratory suspects a possible bias in the lower end of the calibration.

U-234 water

Total U water Permanent Corrective/Preventive Actions or Improvements Filter: The laboratory will be analyzing the sample without dilutions.

The dilutions will only be performed when necessary.

Water: The laboratory will be adding another point to the lower end of the calibration to remove potential bias in that section of the calibration.

The laboratory successfully analyzed these isotopes during the next round of MRAD samples.

CARR 200224-1274 Root Cause Analysis ISO Documentation of PT Failures in Strontium-89-A review of the data and the preparation processes RAD-120 for: did not reveal any errors or possible contributors to the high bias.

In addition, the reported values are 117% and 114% of the

Sr-89 reference value which are with the laboratory's standard

Gross Alpha acceptance criteria of+/- 25% for Laboratory Control Samples.

Tritium-All data and laboratory processes were evaluated, and no errors were found. The Laboratory has concluded that this low bias was an isolated occurrence and that the overall process is within control.

lodine-131- The laboratory has reviewed the data and found no errors. All batch QC samples including a duplicate, met acceptability criteria. The laboratory will continue to investigate all steps of the analytical process.

Permanent Corrective/Preventive Actions or Improvements The Laboratory has concluded that these positive biases were isolate1 occurrences and that the overall process is within control. The lab wil

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CORRECTIVE ACTION ID#

& DISPOSITION PE FAILURE complete PT studies for these parameters as they become available to verify that these were isolated incidences.

CARR191212-1262 Root Cause Analysis ISO Documentation of PT Failures in Upon receipt of the report, an investigation was initiated by our MRAD-31 Quality Department and a Corrective Action (CARR) team assembled. The team consisted of representatives from the affected

Pb-212 areas. The sample preparation and analytical processes were reviewed. This included review of reagents and standards used in the sample preparation steps, calibration records, process control samples, instruments used during analysis and interviews with the analysts.

The investigation determined that the laboratory met all quality control criteria specified in the methods. Additionally, all internal procedures and processes were evaluated and found to have been performed as required. These failures were tracked through GEL's internal non-conformance system.

Lead-212: The data was reviewed and no anomalies noted. The Duplicate result of the original analysis met the acceptance criteria of the study and replication criteria of the laboratory. Laboratory processes were evaluated and no errors were found. The other reported analytes for the method were within the limits of the study.

A definitive contributor to the slightly high bias could not be identified concluding that this was an isolated occurrence.

Permanent Corrective/Preventive Actions or Improvements None at this time. The laboratory will continue to monitor the recoveries of these parameters to ensure that there are no continued issues in the processes CARR191212-1265 Root Cause Analysis ISO Documentation of PT Failures in Upon receipt of the report, an investigation was initiated by our MAPEP-19-MaW41 Quality Department and a Corrective Action (CARR) team assembled. The team consisted of representatives from the affected

Ra-226 laboratory areas. The sample preparation and analytical processes were reviewed. This included review of reagents and standards used in the sample preparation steps, calibration records, process control samples, and interviews with the analysts.

The investigation determined that the laboratory met all quality control criteria specified in each method. Additionally, all internal procedures and policies were performed as required. These failures were tracked throuqh GEL's internal non-conformance system.

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CORRECTIVE ACTION ID#

& DISPOSITION PE FAILURE The laboratory reviewed the data and no errors were found. The preparation and counting processes were reviewed and no anomalies were noted. It was noted that verification counts of the sample preparations were within limits and met laboratory replication criteria Permanent Corrective/Preventive Actions or Improvements None needed at this time. The laboratory must assume unidentified random errors caused the biases because all quality control criteria were met in the batch.

Subsequent analyses of these isotopes for drinking water were acceptable in other PT samples durinq the vear.

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6.2 Environmental TLD QA Environmental dosimetry services for the reporting period of January - December 2020 were provided through Stanford Dosimetry, with TLD processing by the Environmental Dosimetry Company (EDC), Sterling, Massachusetts. The TLD systems at the Environmental Dosimetry Company (EDC) are calibrated and operated to ensure consistent and accurate evaluation of TLDs. The quality of the dosimetric results reported to EDC clients is ensured by in-house performance testing and independent performance testing by EDC clients.

The purpose of the dosimetry quality assurance program is to provide performance documentation of the routine processing of EDC dosimeters. Performance testing provides a statistical measure of the bias and precision of dosimetry processing against a reliable standard, which in turn points out any trends or performance changes. Dosimetry quality control tests are performed on EDC Panasonic 814 Environmental dosimeters. These tests include: (1) the in-house testing program conducted by the EDC QA Officer; and (2) independent test perform by EDC clients. In-house tests are performed using six pairs of 814 dosimeters. A pair is reported as an individual result and six pairs are reported as the mean result.

Excluded from this report are instrumentation checks. Although instrumentation checks represent an important aspect of the quality assurance program, they are not included as process checks in this report.

Instrumentation checks represent between 5-10% of the TLDs processed .

Table 6.2-1 provides a summary of individual dosimeter results evaluated against the EDC internal acceptance criteria for high-energy photons (Cs-137) only. The internal acceptance (tolerance) criteria for the Panasonic Environmental dosimeters are: +/- 15% for bias and+/- 12.8% for precision. During this period, 100% (72/72) of the individual dosimeters evaluated against these criteria met the tolerance limits for accuracy and 100% (72/72) met the criterion for precision.

Table 6.2-2 provides the Bias + Standard deviation results for each group (N=6) of dosimeters evaluated against the internal tolerance criteria. Overall, 100% ( 12/12) of the dosimeter sets evaluated against the internal tolerance performance criteria met these criteria.

Table 6.2-3 presents the independent blind spike results for irradiated dosimeters provided by client utilities during this annual period . All results passed the performance acceptance criterion .

Table 6.2-4 presents the independent blind duplicate results for dosimeters co-located with field dosimeters provided by the client utility (Seabrook Station) during the annual period. All results passed the performance criteria of agreement to within 20% (within 3-sigma) of the field dosimeter.

TABLE 6.2-1 PERCENTAGE OF INDIVIDUAL DOSIMETERS THAT PASSED EDC INTERNAL CRITERIA JANUARY - DECEMBER 2020( 1), (2)

Number % Passed Precision Dosimeter Type % Passed Bias Criteria Tested Criteria Panasonic Environmental 72 100 100

<1>This table summarizes results of tests conducted by EDC.

<2>Environmental dosimeter results are free in air.

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TABLE 6.2-2 MEAN DOSIMETER ANALYSES (N=6)

JANUARY - DECEMBER 2020( 1), ( 2 )

Exposure Standard Tolerance Process Date Mean Bias%

Level Deviation% Limit +/-15%

412812020 37 1.8 1.2 Pass 510212020 94 2.9 1.4 Pass 512012020 56 -0.5 1.4 Pass 712812020 72 4.1 0.6 Pass 810712020 111 4.0 1.3 Pass 9/24/2020 25 -4.6 1.2 Pass 10/24/2020 35 5.2 1.6 Pass 10/28/2020 60 1.6 0.7 Pass 11/18/2020 91 0.5 1.6 Pass 01/21/2021 31 3.8 1.7 Pass 02/09/2021 83 0.3 0.8 Pass 02/16/2021 46 5.3 1.5 Pass

<1>This table summarizes results of tests conducted by EDC for TLDs issued in 2020.

<2> Environmental dosimeter results are free in air.

TABLE 6.2-3

SUMMARY

OF INDEPENDENT DOSIMETER TESTING JANUARY - DECEMBER 2020( 1), (2)

Standard Issuance Period Client Mean Bias% Pass I Fail Deviation%

1st Qtr. 2020 Millstone -3.8 3.0 Pass 2nd Qtr.2020 Seabrook 0.5 1.4 Pass 2nd Qtr.2020 Millstone -3.0 1.6 Pass 3rd Qtr. 2020 Millstone 0.4 2.6 Pass 4th Qtr.2020 PSEG(PNNL) -3.2 0.9 Pass 4th Qtr.2020 Seabrook 6.9 1.9 Pass 4th Qtr.2020 SONGS -8.4 1.3 Pass 4th Qtr.2020 Millstone 3.0 1.9 Pass

<1> Performance criterion is +/- 15%.

<2> Blind spike irradiations using Cs-137

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TABLE 6.2-4

SUMMARY

OF INDEPENDENT BLIND DUPLICATE DOSIMETER TESTING JANUARY - DECEMBER 2020( 1)

%Passed Number Mean Bias Standard Issuance Period Client Precision Tested % Deviation%

Criteria 1st Qtr. 2020 Seabrook 12 1.3 4.9 Pass 2nd Qtr.2020 Seabrook 6 -3.3 1.5 Pass 3rd Qtr. 2020 Seabrook 12 1.1 3.3 Pass 4th Qtr.2020 Seabrook 6 -1.5 2.8 Pass (1) Performance criterion is Bias % within +/- 20% for each test dosimeter.

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7 .0 Land Use Census The Offsite Dose Calculation Manual (ODCM Control 9.2.1) requires that a Land Use Census be conducted annually to identify the location of the nearest residence, milk animal and nearest garden of greater than 50 square meters producing broad leaf vegetation in each of the 16 meteorological sectors within five miles of the plant. The 2020 census was completed in accordance with the requirements of the ODCM. In 2020, a global positioning system was used to determine locations in the off-site environs with respect to the center of the site (Unit 1 Containment).

The nearest resident, garden and milk animal locations identified in the 2020 Land Use Census and their distances are shown in Table 7.0-1. There were no changes in the identification of nearest residents and one change in nearest gardens from last year's census.

There were no new milk producing locations identified within the required 5 miles (8 km) of the plant that were different from those reported in the last year's land use census. As a result, there still remains an insufficient number of milk producing locations to qualify milk sampling as a REMP media per the requirements of ODCM Table A.9.1-1.

The results of this year's census also showed that the sampling locations used in the REMP continue to have the highest calculated dose commitments of available locations. In 2020, broad leaf vegetation continued as part of the sample collection and analysis program due to the absence of sufficient milk producing locations to provide REMP samples. Sampling locations for broad leaf vegetation are at the site boundary near points of highest predicted D/Q. This option continues, as opposed to public owned vegetable gardens located by the land use census, in order to ensure adequate availability of samples for REMP analysis from locations with the highest potential for detecting plant effluents.

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Table 7.0-1 2020 Land Use Census Results (Within 5 Miles)

Nearest Nearest

Nearest Residence Garden Milk Animal Sector (km) (km) (km)

N 2.78 3.99 NNE 3.09 3.20 NE 2.92 4.24 ENE 2.31 2.53 E 2.56 ---

ESE 2.43 ---

SE 2.36 4.69 -

SSE 1.65 ---

s 1.21 1.25 SSW 1.12 1.22 SW 1.13 1.73 WSW 1.87 2.33 w 1.25 1.55 WNW 1.11 3.08 NW 1.22 3.14 6.93 NNW 1.04 2.07 5.32 a a No milking goats at this time.

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Attachment 1: Sample Analysis Data List for 2020 FLAGS A blank Flag field indicates that the measured activity is considered positive as it is greater than the MDC and has no other qualifiers noted.

U: Target isotope was analyzed for but not detected above the MDC and LLD.

UI: Uncertain identification for gamma spectroscopy.

X: Lab-specific qualifier:

(1) False positive due to the presence of radon gas in the water.

M: Reported result is less than the LLD and greater than the MDC.

DL: Measured MDC is greater than the LLD.

DL*: Near miss of MDC being within round-off difference of being greater than the LLD.

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Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/kg) (pCi/kg) (pCi/kg)

AL 05 511607001 5/14/2020 Ac-228 l.98E+Ol 3.62E+Ol 9.49E+Ol u AL 05 511607001 5/14/2020 Ag-108m -2.92E+OO 4.13E+OO l.27E+Ol u AL 05 511607001 5/14/2020 Ag-llOm -2.82E+OO 7.58E+OO 2.36E+Ol u AL 05 511607001 5/14/2020 Ba-140 5.84E+Ol 3.47E+Ol 8.86E+Ol u AL 05 511607001 5/14/2020 Be-7 6.09E+Ol 4.85E+Ol l.67E+02 u AL 05 511607001 5/14/2020 Ce-141 l.89E+OO 6.65E+OO 2.22E+Ol u AL 05 511607001 5/14/2020 Ce-144 -l.38E+Ol 2.44E+Ol 7.89E+Ol u AL 05 511607001 5/14/2020 Co-57 8.15E-Ol 3.14E+OO l.06E+Ol u AL 05 511607001 5/14/2020 Co-58 -8.49E+OO 6.22E+OO l.69E+Ol u AL 05 511607001 5/14/2020 Co-60 2.07E+OO 5.66E+OO l.96E+Ol u AL 05 511607001 5/14/2020 Cr-51 3.27E+Ol 4.43E+Ol l.43E+02 u AL 05 511607001 5/14/2020 Cs-134 l.90E+OO 6.36E+OO 2.llE+Ol u AL 05 511607001 511412020 Cs-137 9.05E+OO 6.14E+OO 2.09E+Ol u AL 05 511607001 5/14/2020 Fe-59 -3.44E+OO l.34E+Ol 4.46E+Ol u AL 05 511607001 5/14/2020 1-131 2.88E+OO 9.82E+OO 3.IOE+Ol u AL 05 511607001 5/14/2020 K-40 7.35E+03 4.58E+02 l.95E+02 AL 05 511607001 5/14/2020 La-140 -3.90E+OO 8.67E+OO 2.66E+Ol u AL 05 511607001 5/14/2020 Mn-54 -3.00E+OO 6.24E+OO l.94E+Ol u AL 05 511607001 5/14/2020 Nb-95 -4.76E+OO 5.39E+OO l.59E+Ol u AL 05 511607001 5/14/2020 Ru-103 3.0IE+OO 4.99E+OO l.72E+Ol u AL 05 511607001 5/14/2020 Ru-106 -4.79E+OO 5.26E+Ol l.55E+02 u AL 05 511607001 5/14/2020 Sb-124 -l.35E+Ol l.15E+Ol 2.85E+Ol u AL 05 511607001 5/14/2020 Sb-125 -l.75E-Ol l.26E+Ol 4.28E+Ol u AL 05 511607001 5/14/2020 Se-75 -2.42E+OO 7.26E+OO l.99E+Ol u AL 05 511607001 5/14/2020 Th-228 l.94E+Ol l.53E+Ol 3.29E+Ol u AL 05 511607001 5/14/2020 Zn-65 l.90E+OO l.65E+Ol 4.99E+Ol u AL 05 511607001 5/14/2020 Zr-95 -7.83E+OO l.05E+Ol 3.17E+Ol u AL 05 529895001 12/9/2020 Ac-228 6.30E+OO 2.35E+Ol 8.50E+Ol u AL 05 529895001 12/9/2020 Ag-108m -5.58E+OO 4.35E+OO 1.26E+Ol u AL 05 529895001 12/9/2020 Ag-llOm -l.06E+Ol 7.82E+OO l.62E+Ol u AL 05 529895001 12/9/2020 Ba-140 9.30E+OO 2.27E+Ol 7.62E+Ol u AL 05 529895001 12/9/2020 Be-7 O.OOE+OO 9.40E+Ol l.33E+02 u AL 05 529895001 12/9/2020 Ce-141 -l.47E+OO 7.76E+OO 2.22E+Ol u AL 05 529895001 12/9/2020 Ce-144 4.32E+Ol 2.95E+Ol 9.45E+Ol u AL 05 529895001 12/9/2020 Co-57 3.96E+OO 4.21E+OO l.36E+Ol u AL 05 529895001 12/9/2020 Co-58 4.25E+OO 4.28E+OO l.48E+Ol u AL 05 529895001 12/9/2020 Co-60 -7.15E+OO 6.84E+OO l.97E+Ol u AL 05 529895001 12/9/2020 Cr-51 O.OOE+OO O.OOE+OO l.36E+02 u AL 05 529895001 12/9/2020 Cs-134 -l.87E+OO 6.34E+OO l.97E+Ol u AL 05 529895001 12/9/2020 Cs-137 -4.43E-Ol 5.49E+OO l.57E+Ol u AL 05 529895001 12/9/2020 Fe-59 -6.20E+OO l.23E+Ol 3.95E+Ol u AL 05 529895001 12/9/2020 I-131 l.58E+OO 8.42E+OO 2.85E+Ol u AL 05 529895001 12/9/2020 K-40 7.82E+03 5.46E+02 l.29E+02 AL 05 529895001 12/9/2020 La-140 3.59E-Ol 5.38E+OO l.78E+Ol u AL 05 529895001 12/9/2020 Mn-54 -3.89E+OO 4.88E+OO l.40E+Ol u AL 05 529895001 12/9/2020 Nb-95 l.55E+Ol 9.52E+OO l.68E+Ol u AL 05 529895001 12/9/2020 Ru-103 -6.07E+OO 5.16E+OO l.50E+Ol u AL 05 529895001 12/9/2020 Ru-106 -4.62E-Ol 4.43E+Ol l.44E+02 u AL 05 529895001 12/9/2020 Sb-124 l.58E+Ol l.26E+Ol 4.60E+Ol u 152

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/kg) (pCi/kg) (pCi/kg)

AL 05 529895001 12/9/2020 Sb-125 5.27E+OO l.07E+Ol 3.65E+Ol u AL 05 529895001 12/9/2020 Se-75 l.29E+OO 5.37E+OO l.85E+Ol u AL 05 529895001 12/9/2020 Th-228 -4.78E+OO l.OIE+Ol 3.38E+Ol u AL 05 529895001 12/9/2020 Zn-65 2.59E+Ol l.66E+Ol 4.65E+Ol u AL 05 529895001 12/9/2020 Zr-95 -4.97E-Ol 8.64E+OO 2.75E+Ol u AL 55 511607002 5/14/2020 Ac-228 2.75E+Ol 2.94E+Ol 5.21E+Ol u AL 55 511607002 5/14/2020 Ag-108m 2.67E-Ol 2.66E+OO 8.82E+OO u AL 55 511607002 5/14/2020 Ag-llOm -3.68E-02 4.96E+OO l.60E+Ol u AL 55 511607002 5/14/2020 Ba-140 l.17E+Ol l.53E+Ol 5.18E+Ol u AL 55 511607002 5114/2020 Be-7 9.47E+Ol 3.60E+Ol 8.02E+Ol AL 55 511607002 5/14/2020 Ce-141 3.24E+OO 9.0IE+OO l.71E+Ol u AL 55 511607002 5/14/2020 Ce-144 3.15E+OO l.73E+Ol 5.88E+Ol u AL 55 511607002 5/14/2020 Co-57 -7.l IE-01 2.29E+OO 7.71E+OO u AL 55 511607002 5/14/2020 Co-58 -4.77E+OO 3.33E+OO 9.0IE+OO u AL 55 511607002 5/14/2020 Co-60 -2.30E-Ol 3.64E+OO l.15E+Ol u AL 55 511607002 5/14/2020 Cr-51 -4.00E+Ol 2.87E+Ol 8.45E+Ol u AL 55 511607002 5/14/2020 Cs-134 -1.28E+OO 3.59E+OO l.13E+Ol u AL 55 511607002 5/14/2020 Cs-137 l.57E+OO 3.15E+OO l.05E+Ol u AL 55 511607002 5/14/2020 Fe-59 8.42E+OO 8.1 IE+OO 2.71E+Ol u AL 55 511607002 5/14/2020 1-131 3.64E+OO 6.llE+OO 2.06E+Ol u AL 55 511607002 5/14/2020 K-40 4.90E+03 3.36E+02 l.06E+02 AL 55 511607002 5/14/2020 La-140 -2.42E+OO 5.18E+OO l.66E+Ol u AL 55 511607002 5/14/2020 Mn-54 -4.58E+OO 3.27E+OO 8.91E+OO u AL 55 511607002 5/14/2020 Nb-95 2.96E+OO 3.35E+OO l.12E+Ol u AL 55 511607002 5/14/2020 Ru-103 2.26E+OO 2.98E+OO l.OIE+Ol u AL 55 511607002 5/14/2020 Ru-106 l.86E+Ol 2.48E+Ol 8.37E+Ol u AL 55 511607002 5/14/2020 Sb-124 -l.94E-Ol 6.25E+OO 2.IOE+Ol u AL 55 511607002 5/14/2020 Sb-125 -9.41E+OO 8.87E+OO 2.70E+Ol u AL 55 511607002 5/14/2020 Se-75 l.72E+OO 3.85E+OO l.30E+Ol u AL 55 511607002 5/14/2020 Th-228 4.llE+OO 9.65E+OO 2.22E+Ol u AL 55 511607002 5/14/2020 Zn-65 4.36E+OO 7.83E+OO 2.59E+Ol u AL 55 511607002 5/14/2020 Zr-95 -8.92E-Ol 5.46E+OO l.75E+Ol u AL 55 529895002 12/9/2020 Ac-228 7.88E+Ol 3.32E+Ol 9.23E+Ol u AL 55 529895002 12/9/2020 Ag-108m -2.75E+OO 3.95E+OO l.25E+Ol u AL 55 529895002 12/9/2020 Ag-llOm 6.0IE+OO 6.95E+OO 2.46E+Ol u AL 55 529895002 12/9/2020 Ba-140 -7.46E+OO 2.21E+Ol 7.09E+Ol u AL 55 529895002 12/9/2020 Be-7 2.76E+02 8.84E+Ol l.27E+02 AL 55 529895002 12/9/2020 Ce-141 4.94E+OO 6.91E+OO 2.28E+Ol u AL 55 529895002 12/9/2020 Ce-144 -l.77E+Ol 2.46E+Ol 7.64E+Ol u AL 55 529895002 12/9/2020 Co-57 4.57E+OO 3.42E+OO l.13E+Ol u AL 55 529895002 12/9/2020 Co-58 -7.66E+OO 5.45E+OO l.41E+Ol u AL 55 529895002 12/9/2020 Co-60 3.05E+OO 5.28E+OO l.83E+Ol u AL 55 529895002 12/9/2020 Cr-51 -3.70E+Ol 3.89E+Ol l.23E+02 u AL 55 529895002 12/9/2020 Cs-134 -2.34E+OO 5.18E+OO l.57E+Ol u AL 55 529895002 12/9/2020 Cs-137 -1.23E+Ol 6.73E+OO l.65E+Ol u AL 55 529895002 12/9/2020 Fe-59 5.88E+OO l.OOE+Ol 3.48E+Ol u AL 55 529895002 12/9/2020 1-131 9.19E+OO 7.98E+OO 2.76E+Ol u AL 55 529895002 12/9/2020 K-40 8.00E+03 4.98E+02 l.64E+02 AL 55 529895002 12/9/2020 La-140 -l.33E+Ol 7.92E+OO l.60E+Ol u 153

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/kg) (pCi/kg) (pCi/kg)

AL 55 529895002 12/9/2020 Mn-54 6.71E+OO 5.49E+OO l.71E+Ol u AL 55 529895002 12/9/2020 Nb-95 -l.47E+OO 5.53E+OO l.73E+Ol u AL 55 529895002 12/9/2020 Ru-103 -3.38E+OO 4.86E+OO 1.41E+Ol u AL 55 529895002 12/9/2020 Ru-106 l.16E+Ol 4.34E+Ol l.44E+02 u AL 55 529895002 12/9/2020 Sb-124 -1.27E+Ol 1.21E+Ol 3.llE+Ol u AL 55 529895002 12/9/2020 Sb-125 -8.48E+OO 1.04E+Ol 3.23E+Ol u AL 55 529895002 12/9/2020 Se-75 7.85E+OO 6.13E+OO l.97E+Ol u AL 55 529895002 12/9/2020 Th-228 5.08E+OO l.02E+Ol 3.37E+Ol u AL 55 529895002 12/9/2020 Zn-65 4.91E+OO 1.44E+Ol 4.88E+Ol u AL 55 529895002 12/9/2020 Zr-95 -l.36E+OO 8.67E+OO 2.42E+Ol u 154

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/m3) (pCi/m3) (pCi/m3)

AP 01 501552001 1115/2020 BETA 2.30E-02 l.19E-03 l.15E-03 AP 01 502825001 l/29/2020 BETA 2.14E-02 l.lOE-03 1.04E-03 AP 01 504483001 2/12/2020 BETA 2.09E-02 l.09E-03 l.OlE-03 AP 01 505599001 2/26/2020 BETA 3.72E-02 l.55E-03 l .16E-03 AP 01 506904001 3/11/2020 BETA 2.24E-02 l.06E-03 8.81E-04 AP 01 508060001 3/25/2020 BETA 2.19E-02 l.04E-03 9.89E-04 AP 01 510636001 3/25/2020 Ac-228 -5.12E-04 5.18E-04 l.66E-03 u AP 01 510636001 3/25/2020 Ag-108m -l.42E-05 8.55E-05 2.72E-04 u AP 01 510636001 3/25/2020 Ag-llOm 2.04E-04 l.83E-04 6.44E-04 u AP 01 510636001 3/25/2020 Ba-140 -8.0lE-03 2.88E-02 8.84E-02 u AP 01 510636001 3/25/2020 Be-7 l.26E-Ol 9.56E-03 6.79E-03 AP 01 510636001 3/25/2020 Ce-141 4.62E-05 l.29E-03 2.lOE-03 u AP 01 510636001 3/25/2020 Ce-144 2.69E-04 4.82E-04 l.68E-03 u AP 01 510636001 3/25/2020 Co-57 3.23E-05 6.22E-05 2.17E-04 u AP 01 510636001 3/25/2020 Co-58 -l.97E-04 l.67E-04 4.42E-04 u AP 01 510636001 3/25/2020 Co-60 2.04E-05 l.12E-04 3.86E-04 u AP 01 510636001 3/25/2020 Cr-51 2.02E-03 5.84E-03 l.95E-02 u AP 01 510636001 3/25/2020 Cs-134 4.50E-05 l.24E-04 4.llE-04 u AP 01 510636001 3/25/2020 Cs-137 7.78E-05 9.l lE-05 2.96E-04 u AP 01 510636001 3/25/2020 Fe-59 -4.27E-05 5.52E-04 l.77E-03 u AP 01 510636001 3/25/2020 1-131 -3.85E-03 l.28E-Ol O.OOE+OO u AP 01 510636001 3/25/2020 K-40 l.36E-03 l.51E-03 5.51E-03 u AP 01 510636001 3/25/2020 La-140 6.99E-03 l.31E-02 4.63E-02 u AP 01 510636001 3/25/2020 Mn-54 -2.89E-06 l.26E-04 4.17E-04 u AP 01 510636001 3/25/2020 Nb-95 3.20E-04 3.38E-04 l.05E-03 u AP 01 510636001 3/25/2020 Ru-103 -8.35E-06 3.12E-04 9.93E-04 u AP 01 510636001 3/25/2020 Ru-106 l.83E-04 9.53E-04 3.26E-03 u AP 01 510636001 3/25/2020 Sb-124 -l.04E-04 6.88E-04 2.23E-03 u AP 01 510636001 3/25/2020 Sb-125 -6.65E-05 2.54E-04 8.0lE-04 u AP 01 510636001 3/25/2020 Se-75 3.15E-04 l.74E-04 5.78E-04 u AP 01 510636001 3/25/2020 Th-228 2.33E-04 3.38E-04 4.03E-04 u AP 01 510636001 3/25/2020 Zn-65 -l.57E-04 3.03E-04 9.13E-04 u AP 01 510636001 3/25/2020 Zr-95 -3.07E-04 3.77E-04 1.12E-03 u AP 01 509289001 4/9/2020 BETA 8.50E-03 7.32E-04 9.75E-04 M AP 01 510087001 4/22/2020 BETA 2.57E-02 l.29E-03 l.13E-03 AP 01 510960001 5/6/2020 BETA l.84E-02 9.94E-04 9.66E-04 AP 01 511920001 5/20/2020 BETA l.62E-02 9.57E-04 9.58E-04 AP 01 512893001 6/3/2020 BETA l.50E-02 9.34E-04 l.03E-03 AP 01 514085001 6/17/2020 BETA l.96E-02 l.09E-03 l.05E-03 AP 01 515124001 7/112020 BETA 2.60E-02 l.38E-03 l.46E-03 AP 01 517014001 7/112020 Ac-228 2.75E-04 8.07E-04 l.53E-03 u AP 01 517014001 7/112020 Ag-108m -l.75E-04 8.33E-05 l.81E-04 u AP 01 517014001 7/112020 Ag-llOm -2.84E-05 l.59E-04 5.02E-04 u AP 01 517014001 7/112020 Ba-140 -2.61E-03 2.00E-02 6.63E-02 u AP 01 517014001 7/112020 Be-7 l.36E-Ol 1.0lE-02 7.02E-03 AP 01 517014001 7/112020 Ce-141 -3.14E-04 5.17E-04 l.65E-03 u AP 01 517014001 7/112020 Ce-144 -2.05E-04 4.55E-04 l.25E-03 u 155

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/m3) (pCi/m3) (pCi/m3)

AP 01 517014001 7/1/2020 Co-57 -5.15E-05 6.17E-05 1.80E-04 u AP 01 517014001 7/1/2020 Co-58 -1.09E-04 1.78E-04 5.30E-04 u AP 01 517014001 7/1/2020 Co-60 1.13E-04 9.55E-05 3.55E-04 u AP 01 517014001 7/1/2020 Cr-51 -2.62E-03 4.60E-03 1.43E-02 u AP 01 517014001 7/1/2020 Cs-134 2.34E-04 1.18E-04 4.IOE-04 u AP 01 517014001 7/1/2020 Cs-137 -3.16E-05 9.49E-05 3.03E-04 u AP 01 517014001 7/1/2020 Fe-59 7.36E-05 5.40E-04 1.83E-03 u AP 01 517014001 7/1/2020 I-131 -6.43E-02 8.63E-02 O.OOE+OO u AP 01 517014001 7/1/2020 K-40 1.52E-03 1.78E-03 6.24E-03 u AP 01 517014001 7/1/2020 La-140 -1.20E-04 1.27E-02 4.09E-02 u AP 01 517014001 7/1/2020 Mn-54 -1.49E-05 1.17E-04 3.72E-04 u AP 01 517014001 7/1/2020 Nb-95 4.74E-04 2.70E-04 6.71E-04 u AP 01 517014001 7/1/2020 Ru-103 -2.14E-05 2.96E-04 8.75E-04 u AP 01 517014001 7/1/2020 Ru-106 3.38E-04 9.71E-04 3.29E-03 u AP 01 517014001 7/1/2020 Sb-124 9.22E-04 6.40E-04 2.43E-03 u AP 01 517014001 7/1/2020 Sb-125 1.96E-04 2.50E-04 7.53E-04 u AP 01 517014001 7/1/2020 Se-75 -1.20E-04 1.31E-04 3.99E-04 u AP 01 517014001 7/1/2020 Th-228 3.13E-05 1.47E-04 4.26E-04 u AP 01 517014001 7/1/2020 Zn-65 -4.57E-04 2.85E-04 7.0IE-04 u AP 01 517014001 7/1/2020 Zr-95 4.71E-05 3.04E-04 8.93E-04 u AP 01 516358001 7/17/2020 BETA 1.08E-02 8.92E-04 1.17E-03 AP 01 517178001 7/29/2020 BETA _ 4.03E-02 1.91E-03 1.66E-03 AP 01 518829001 8/12/2020 BETA 4.59E-02 4.49E-03 6.93E-03 AP 01 519921001 8/26/2020 BETA 2.93E-02 1.31E-03 1.04E-03 AP 01 521451001 9/9/2020 BETA 2.31E-02 1.1 IE-03 9.59E-04 AP 01 522475001 9/23/2020 BETA 2.llE-02 9.91E-04 8.24E-04 AP 01 526420001 9/23/2020 Ac-228 6.87E-04 5.84E-04 1.98E-03 u AP 01 526420001 9/23/2020 Ag-108m 9.23E-05 8.41E-05 2.68E-04 u AP 01 526420001 9/23/2020 Ag-llOm 8.14E-05 1.70E-04 6.00E-04 u AP 01 526420001 9/23/2020 Ba-140 5.37E-02 5.04E-02 1.72E-01 u AP 01 526420001 9/23/2020 Be-7 1.40E-01 1.15E-02 8.40E-03 AP 01 526420001 9/23/2020 Ce-141 1.75E-03 1.38E-03 2.21E-03 u AP 01 526420001 9/23/2020 Ce-144 -4.37E-05 5.50E-04 1.71E-03 u AP 01 526420001 9/23/2020 Co-57 -3.46E-06 7.04E-05 2.20E-04 u AP 01 526420001 9/23/2020 Co-58 -5.08E-05 2.75E-04 8.53E-04 u AP 01 526420001 9/23/2020 Co-60 -6.49E-05 1.40E-04 4.30E-04 u AP 01 526420001 9/23/2020 Cr-51 -5.99E-04 6.89E-03 2.29E-02 u AP 01 526420001 9/23/2020 Cs-134 -1.39E-04 1.50E-04 4.17E-04 u AP 01 526420001 9/23/2020 Cs-137 -5.52E-05 1.24E-04 3.30E-04 u AP 01 526420001 9/23/2020 Fe-59 8.77E-04 6.66E-04 2.52E-03 u AP 01 526420001 9/23/2020 I-131 -6.22E-02 2.82E-01 O.OOE+OO u AP 01 526420001 9/23/2020 K-40 4.31E-03 2.87E-03 4.54E-03 u AP 01 526420001 9/23/2020 La-140 -1.31E-02 1.88E-02 5.30E-02 u AP 01 526420001 9/23/2020 Mn-54 1.19E-04 1.29E-04 4.26E-04 u AP 01 526420001 9/23/2020 Nb-95 2.15E-04 2.86E-04 9.64E-04 u AP 01 526420001 9/23/2020 Ru-103 -4.18E-04 5.00E-04 1.29E-03 u AP 01 526420001 9/23/2020 Ru-106 -1.96E-04 1.18E-03 3.75E-03 u AP 01 526420001 9/23/2020 Sb-124 -7.80E-04 6.99E-04 1.63E-03 u AP 01 526420001 9/23/2020 Sb-125 5.00E-04 2.94E-04 8.98E-04 u 156

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/m 3 ) (pCi/m 3 ) (pCi/m 3 )

AP 01 526420001 9/23/2020 Se-75 l.48E-04 l .87E-04 6.44E-04 u AP 01 526420001 9/23/2020 Th-228 4.31£-04 2.76E-04 6.79E-04 u AP 01 526420001 9/23/2020 Zn-65 7.82E-05 3.18E-04 l.09E-03 u AP 01 526420001 9/23/2020 Zr-95 -3.28E-04 4.91E-04 I .43E-03 u AP 01 523935001 1017/2020 BETA 3.66E-02 l.30E-03 8.19E-04 AP 01 525295001 10/21/2020 BETA 2.41E-02 l.08E-03 8.87E-04 AP 01 527529001 11/6/2020 BETA 2.58E-02 l.03E-03 7.52E-04 AP 01 528278001 11/18/2020 BET A 5. l 5E-02 l.68E-03 l.05E-03 AP 01 529289001 12/2/2020 BETA 2.76E-02 l .15E-03 9.09E-04 AP 01 530489001 12/16/2020 BETA 3.0IE-02 1.20E-03 8.56E-04 AP 01 531226001 12/30/2020 BETA 2.82E-02 l .15E-03 8.36E-04 AP 01 533257001 12/30/2020 Ac-228 3.46E-04 4.34E-04 I. l 7E-03 u AP 01 533257001 12/30/2020 Ag-108m -l.24E-05 4.12E-05 l.35E-04 u AP 01 533257001 12/30/2020 Ag-1 lOm -l.3 lE-04 l.05E-04 2.69E-04 u AP 01 533257001 12/30/2020 Ba-140 -l .20E-02 l.l 9E-02 3.48E-02 u AP 01 533257001 12/30/2020 Be-7 l.07E-Ol 7.81E-03 3.83E-03 AP 01 533257001 12/30/2020 Ce-141 4.88E-04 3.02E-04 9.41E-04 u AP 01 533257001 12/30/2020 Ce-144 l.49E-04 3.05E-04 9.35E-04 u AP 01 533257001 12/30/2020 Co-57 -3.48E-05 4.0IE-05 l. JOE-04 u AP 01 533257001 12/30/2020 Co-58 -l.l lE-04 l.14E-04 3.15E-04 u AP 01 533257001 12/30/2020 Co-60 4.59E-05 6.21E-05 2.28E-04 u AP 01 533257001 12/30/2020 Cr-51 2.29E-04 2.89E-03 9.92E-03 u AP 01 533257001 12/30/2020 Cs-134 -3.24E-05 7.04E-05 2. I 5E-04 u AP 01 533257001 12/30/2020 Cs-137 -3.38E-05 6.08E-05 l.87E-04 u AP 01 533257001 12/30/2020 Fe-59 -4.67E-05 3.95E-04 1.23E-03 u AP 01 533257001 12/30/2020 1-131 -l.35E-02 3.25E-02 l.07E-OI u AP 01 533257001 12/30/2020 K-40 O.OOE+OO l .53E-03 2.20E-03 u AP 01 533257001 12/30/2020 La-140 2.53E-03 5.03E-03 l.78E-02 u AP 01 533257001 12/30/2020 Mn-54 9.96E-05 6.69E-05 1.82E-04 u AP 01 533257001 12/30/2020 Nb-95 -l.56E-04 1.50E-04 4.24E-04 u AP 01 533257001 12/30/2020 Ru-I 03 2.42E-05 1.75E-04 5.92E-04 u AP 01 533257001 12/30/2020 Ru-I 06 -1.02E-03 6.28E-04 l.59E-03 u AP 01 533257001 12/30/2020 Sb-124 3.13E-04 3.18E-04 1.21E-03 u AP 01 533257001 12/30/2020 Sb-125 l.70E-05 l.37E-04 4.67E-04 u AP 01 533257001 12/30/2020 Se-75 -3.66E-05 l.09E-04 3.31E-04 u AP 01 533257001 12/30/2020 Th-228 O.OOE+OO 2.37E-04 4.30E-04 u AP 01 533257001 12/30/2020 Zn-65 2.95E-04 1.57E-04 5.90E-04 u AP 01 533257001 12/30/2020 Zr-95 2.96E-04 2.llE-04 7.17E-04 u AP 02 501552002 111512020 BETA 1.98E-02 1.03E-03 9.66E-04 AP 02 502825002 1/29/2020 BETA l.99E-02 l.04E-03 9.97E-04 AP 02 504483002 2/12/2020 BETA 2.64E-02 l .35E-03 l.25E-03 AP 02 505599002 2/26/2020 BETA 3.43E-02 l.43E-03 1.08E-03 AP 02 506904002 3/11/2020 BET A 2.11 E-02 1.11 E-03 l.02E-03 AP 02 508060002 3/25/2020 BET A 2. lOE-02 l. lOE-03 1.06E-03 AP 02 510636002 3/25/2020 Ac-228 l .38E-03 7.87E-04 2.05E-03 u AP 02 510636002 3/25/2020 Ag- I 08m 4.90E-06 7.95E-05 2.67E-04 u 157

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/m3) (pCi/m3 ) (pCi/m3)

AP 02 510636002 3/25/2020 Ag-llOm 2.20E-04 1.57E-04 5.89E-04 u AP 02 510636002 312512020 Ba-140 -4.40E-04 3.36E-02 l.IOE-01 u AP 02 510636002 3/25/2020 Be-7 1.31E-01 1.02E-02 7.72E-03 AP 02 510636002 312512020 Ce-141 -9.29E-04 7.24E-04 1.88E-03 u AP 02 510636002 312512020 Ce-144 8.68E-04 5.88E-04 l.85E-03 u AP 02 510636002 312512020 Co-57 -4.57E-05 6.38E-05 1.98E-04 u AP 02 510636002 312512020 Co-58 1.31E-04 2.61E-04 8.69E-04 u AP 02 510636002 312512020 Co-60 3.59E-05 l.19E-04 4.07E-04 u AP 02 510636002 312512020 Cr-51 -2.99E-04 6.28E-03 2.14E-02 u AP 02 510636002 312512020 Cs-134 l.29E-04 1.47E-04 5.00E-04 u AP 02 510636002 3/25/2020 Cs-137 -1.09E-04 l.30E-04 3.78E-04 u AP 02 510636002 3/2512020 Fe-59 2.93E-04 8.49E-04 2.92E-03 u AP 02 510636002 3/25/2020 I-131 O.OOE+OO 1.56E-Ol 0.00E+OO UI AP 02 510636002 3/25/2020 K-40 2.10E-03 2.50E-03 4.68E-03 u AP 02 510636002 3/25/2020 La-140 7.46E-03 1.60E-02 5.47E-02 u AP 02 510636002 3/25/2020 Mn-54 -1.IOE-05 1.28E-04 4.31E-04 u AP 02 510636002 3/25/2020 Nb-95 3.62E-04 2.29E-04 7.91E-04 u AP 02 510636002 3/25/2020 Ru-103 3.00E-05 3.84E-04 l.28E-03 u AP 02 510636002 3/25/2020 Ru-106 -1.86E-03 l.13E-03 2.47E-03 u AP 02 510636002 3/25/2020 Sb-124 9.08E-05 5.0IE-04 1.76E-03 u AP 02 510636002 3/25/2020 Sb-125 6.74E-05 2.57E-04 8.75E-04 u AP 02 510636002 312512020 Se-75 1.62E-04 1.92E-04 6.23E-04 u AP 02 510636002 3/25/2020 Th-228 5.68E-04 2.90E-04 6.41E-04 u AP 02 510636002 3/25/2020 Zn-65 -2.21E-04 3.06E-04 9.00E-04 u AP 02 510636002 312512020 Zr-95 -4.31E-04 5.16E-04 1.22E-03 u AP 02 509289002 41912020 BETA l.30E-02 8.31E-04 8.92E-04 AP 02 510087002 4/22/2020 BETA 2.04E-02 l.03E-03 1.0IE-03 AP 02 510960002 51612020 BETA 2.02E-02 1.07E-03 9.37E-04 AP 02 511920002 512012020 BETA 1.82E-02 9.56E-04 8.89E-04 AP 02 512893002 6/3/2020 BETA l.50E-02 8.80E-04 9.23E-04 AP 02 514085002 611712020 BETA 1.82E-02 1.00E-03 1.08E-03 AP 02 515124002 7/112020 BETA 2.21E-02 l.12E-03 1.04E-03 AP 02 517014002 71112020 Ac-228 5.35E-04 4.67E-04 1.46E-03 u AP 02 517014002 71112020 Ag-108m 5.72E-05 7.21E-05 2.19E-04 u AP 02 517014002 71112020 Ag-llOm 1.41E-04 1.30E-04 4.67E-04 u AP 02 517014002 71112020 Ba-140 2.16E-03 2.31E-02 6.88E-02 u AP 02 517014002 71112020 Be-7 l.18E-01 9.20E-03 5.59E-03 AP 02 517014002 711/2020 Ce-141 3.85E-04 4.87E-04 1.64E-03 u AP 02 517014002 71112020 Ce-144 -2.61E-05 4.59E-04 1.52E-03 u AP 02 517014002 71112020 Co-57 6.91E-05 5.98E-05 2.02E-04 u AP 02 517014002 71112020 Co-58 2.18E-04 1.86E-04 6.60E-04 u AP 02 517014002 71112020 Co-60 -l.86E-06 l.13E-04 3.69E-04 u AP 02 517014002 7/1/2020 Cr-51 3.31E-03 4.79E-03 1.59E-02 u AP 02 517014002 71112020 Cs-134 7.35E-05 8.51E-05 3.05E-04 u AP 02 517014002 71112020 Cs-137 8.06E-05 8.36E-05 2.97E-04 u AP 02 517014002 71112020 Fe-59 -7.19E-04 5.35E-04 l.36E-03 u AP 02 517014002 71112020 I-131 O.OOE+OO 8.30E-02 0.00E+OO UI AP 02 517014002 71112020 K-40 -3.0IE-03 2.17E-03 4.04E-03 u AP 02 517014002 71112020 La-140 -1.66E-02 l.07E-02 2.39E-02 u 158

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/m3) (pCi/m3) (pCi/m 3)

AP 02 517014002 7/112020 Mn-54 9.60E-05 9.56E-05 3.41E-04 u AP 02 517014002 7/1/2020 Nb-95 3.94E-05 2.33E-04 7.93E-04 u AP 02 517014002 7/112020 Ru-103 -4.22E-04 2.92E-04 7.43E-04 u AP 02 517014002 7/112020 Ru-106 2.67E-04 7.44E-04 2.33E-03 u AP 02 517014002 7/112020 Sb-124 -1.48E-04 5.64E-04 l.75E-03 u AP 02 517014002 7/l/2020 Sb-125 6.23E-04 2.88E-04 7.34E-04 u AP 02 517014002 7/112020 Se-75 l.70E-06 l.39E-04 4.52E-04 u AP 02 517014002 7/l/2020 Th-228 3.06E-04 2.13E-04 5.IOE-04 u AP 02 517014002 7/112020 Zn-65 3.41E-04 2.35E-04 8.05E-04 u AP 02 517014002 7/112020 Zr-95 -1.57E-04 2.73E-04 8.54E-04 u AP 02 516358002 7/17/2020 BETA l.47E-02 8.66E-04 8.66E-04 AP 02 517178002 7/29/2020 BETA 3.0IE-02 1.44E-03 l.21E-03 AP 02 518829002 8/12/2020 BETA 2.99E-02 1.25E-03 l.IOE-03 AP 02 519921002 8/26/2020 BETA 2.56E-02 l.16E-03 l.06E-03 AP 02 521451002 9/9/2020 BETA l.94E-02 l.02E-03 9.71E-04 AP 02 522475002 9/23/2020 BETA l.81E-02 l.OIE-03 l.09E-03 AP 02 526420002 9/23/2020 Ac-228 l.82E-03 l.03E-03 2.04E-03 u AP 02 526420002 9/23/2020 Ag-108m 2.08E-04 l.OIE-04 3.23E-04 u AP 02 526420002 9/23/2020 Ag-llOm -9.25E-05 l.71E-04 5.37E-04 u AP 02 526420002 9/23/2020 Ba-140 l.llE-01 5.78E-02 l.85E-01 u AP 02 526420002 9/23/2020 Be-7 l.20E-01 9.39E-03 8.97E-03 AP 02 526420002 9/23/2020 Ce-141 O.OOE+OO l.73E-03 3.0IE-03 u AP 02 526420002 9/23/2020 Ce-144 -5.41E-04 6.68E-04 2.16E-03 u AP 02 526420002 9/23/2020 Co-57 -2.34E-05 8.07E-05 2.72E-04 u AP 02 526420002 9/23/2020 Co-58 l.28E-04 3.00E-04 8.54E-04 u AP 02 526420002 9/23/2020 Co-60 l.39E-04 l.16E-04 4.IOE-04 u AP 02 526420002 9/23/2020 Cr-51 l.16E-02 8.08E-03 2.57E-02 u AP 02 526420002 9/23/2020 Cs-134 9.36E-07 1.47E-04 4.46E-04 u AP 02 526420002 9/23/2020 Cs-137 -6.52E-06 l.03E-04 3.29E-04 u AP 02 526420002 9/23/2020 Fe-59 l.37E-03 9.96E-04 3.34E-03 u AP 02 526420002 9/23/2020 1-131 O.OOE+OO 2.28E-01 O.OOE+OO UI AP 02 526420002 9/23/2020 K-40 3.61E-03 2.19E-03 3.86E-03 u AP 02 526420002 9/23/2020 La-140 -1.36E-02 1.89E-02 5.68E-02 u AP 02 526420002 9/23/2020 Mn-54 -2.IOE-05 l.37E-04 4.51E-04 u AP 02 526420002 9/23/2020 Nb-95 2.05E-04 2.29E-04 7.92E-04 u AP 02 526420002 9/23/2020 Ru-103 2.07E-04 4.54E-04 1.52E-03 u AP 02 526420002 9/23/2020 Ru-106 l.66E-04 l.07E-03 3.48E-03 u AP 02 526420002 9/23/2020 Sb-124 -4.76E-04 7.35E-04 2.20E-03 u AP 02 526420002 9/23/2020 Sb-125 -5.29E-06 2.60E-04 8.66E-04 u AP 02 526420002 9/23/2020 Se-75 5.17E-04 2.40E-04 7.33E-04 u AP 02 526420002 9/23/2020 Th-228 6.17E-04 4.15E-04 7.41E-04 u AP 02 526420002 9/23/2020 Zn-65 -3.35E-05 3.71E-04 l.07E-03 u AP 02 526420002 9/23/2020 Zr-95 -5.70E-04 4.25E-04 l.22E-03 u AP 02 523935002 1017/2020 BETA 2.89E-02 l.29E-03 l.09E-03 AP 02 525295002 10/2112020 BETA 2.23E-02 l.1 IE-03 9.41E-04 AP 02 527529002 11/6/2020 BETA 2.38E-02 l.12E-03 9.29E-04 AP 02 528278002 11118/2020 BETA 4.32E-02 l.75E-03 1.29E-03 159

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/m3) (pCi/m3 ) (pCi/m3)

AP 02 529289002 12/2/2020 BETA 2.33E-02 l.26E-03 1.18E-03 AP 02 530489002 12/16/2020 BETA 2.21E-02 l.23E-03 1.17E-03 AP 02 531226002 12/30/2020 BETA 2.03E-02 l.07E-03 9.87E-04 AP 02 533257002 12/30/2020 Ac-228 5.43E-04 5.19E-04 l.91E-03 u AP 02 533257002 12/30/2020 Ag-108m 5.52E-05 7.50E-05 2.58E-04 u AP 02 533257002 12/30/2020 Ag-llOm l.04E-04 l.70E-04 5.71E-04 u AP 02 533257002 12/30/2020 Ba-140 -2.53E-03 2.llE-02 6.85E-02 u AP 02 533257002 12/30/2020 Be-7 l.05E-01 8.14E-03 6.21E-03 AP 02 533257002 12/30/2020 Ce-141 -4.40E-04 5.65E-04 l.68E-03 u AP 02 533257002 12/30/2020 Ce-144 -7.04E-04 5.43E-04 l.51E-03 u AP 02 533257002 12/30/2020 Co-57 -8.13E-06 6.30E-05 l.99E-04 u AP 02 533257002 12/30/2020 Co-58 5.89E-05 l.76E-04 5.82E-04 u AP 02 533257002 12/30/2020 Co-60 -8.95E-05 5.58E-05 O.OOE+OO u AP 02 533257002 12/30/2020 Cr-51 -8.31E-03 4.50E-03 1.18E-02 u AP 02 533257002 12/30/2020 Cs-134 -2.52E-04 1.28E-04 2.23E-04 u AP 02 533257002 12/30/2020 Cs-137 4.93E-05 l.OlE-04 3.38E-04 u AP 02 533257002 12/30/2020 Fe-59 -5.13E-04 6.52E-04 l.88E-03 u AP 02 533257002 12/30/2020 I-131 -l.03E-01 6.38E-02 1.72E-01 u AP 02 533257002 12/30/2020 K-40 2.64E-04 l.66E-03 6.30E-03 u AP 02 533257002 12/30/2020 La-140 -8.33E-03 l.07E-02 3.08E-02 u AP 02 533257002 12/30/2020 Mn-54 -8.41E-05 l.12E-04 3.19E-04 u AP 02 533257002 12/30/2020 Nb-95 -l.OlE-04 l.91E-04 5.68E-04 u AP 02 533257002 12/30/2020 Ru-103 -l.03E-04 3.31E-04 l.06E-03 u AP 02 533257002 12/30/2020 Ru-106 6.79E-04 9.53E-04 3.24E-03 u AP 02 533257002 12/30/2020 Sb-124 5.95E-05 6.13E-04 2.02E-03 u AP 02 533257002 12/30/2020 Sb-125 -9.62E-06 2.19E-04 7.26E-04 u AP 02 533257002 1213012020 Se-75 6.14E-05 l.43E-04 4.96E-04 u AP 02 533257002 12/30/2020 Th-228 5.31E-04 3.02E-04 7.28E-04 u AP 02 533257002 12/30/2020 Zn-65 -3.43E-05 2.42E-04 7.98E-04 u AP 02 533257002 12/30/2020 Zr-95 4.17E-04 3.66E-04 1.27E-03 u AP 03 501552003 111512020 BETA l.92E-02 l.04E-03 9.78E-04 AP 03 502825003 112912020 BETA 2.50E-02 l.21E-03 l.lOE-03 AP 03 504483003 2/12/2020 BETA 2.44E-02 l.24E-03 1.14E-03 AP 03 505599003 212612020 BETA 3.32E-02 l.40E-03 l.08E-03 AP 03 506904003 311112020 BETA 2.73E-02 l.21E-03 9.91E-04 AP 03 508060003 312512020 BETA 2.38E-02 l.14E-03 9.83E-04 AP 03 510636003 312512020 Ac-228 -4.43E-04 5.85E-04 1.81E-03 u AP 03 510636003 312512020 Ag-108m 7.59E-05 7.67E-05 2.69E-04 u AP 03 510636003 312512020 Ag-llOm 4.33E-05 2.27E-04 6.61E-04 u AP 03 510636003 3/25/2020 Ba-140 l.60E-02 2.44E-02 8.58E-02 u AP 03 510636003 312512020 Be-7 l.29E-01 l.OlE-02 8.09E-03 AP 03 510636003 312512020 Ce-141 l.25E-03 l.06E-03 1.96E-03 u AP 03 510636003 3/25/2020 Ce-144 1.69E-04 6.22E-04 1.86E-03 u AP 03 510636003 312512020 Co-57 -5.14E-05 6.51E-05 1.95E-04 u AP 03 510636003 3/25/2020 Co-58 7.59E-05 2.39E-04 7.94E-04 u AP 03 510636003 3/25/2020 Co-60 -2.68E-05 l.03E-04 3.29E-04 u AP 03 510636003 3/25/2020 Cr-51 -6.08E-03 6.04E-03 l.88E-02 u 160

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/m3) (pCi/m3 ) (pCi/m3 )

AP 03 510636003 3/25/2020 Cs-134 1.82E-05 l.19E-04 3.89E-04 u AP 03 510636003 3/25/2020 Cs-137 -3.06E-05 9.79E-05 3.07E-04 u AP 03 510636003 3/25/2020 Fe-59 -5.47E-04 5.88E-04 1.64E-03 u AP 03 510636003 3/25/2020 I-131 -1.07E-01 l.38E-01 O.OOE+OO u AP 03 510636003 3/25/2020 K-40 O.OOE+OO 2.07E-03 4.06E-03 u AP 03 510636003 3/25/2020 La-140 l.53E-04 1.25E-02 4.llE-02 u AP 03 510636003 3/25/2020 Mn-54 8.62E-06 1.26E-04 4.06E-04 u AP 03 510636003 3/25/2020 Nb-95 6.77E-05 2.30E-04 7.67E-04 u AP 03 510636003 3/25/2020 Ru-103 2.91E-05 3.22E-04 1.08E-03 u AP 03 510636003 3/25/2020 Ru-106 4.63E-04 9.53E-04 3.06E-03 u AP 03 510636003 3/25/2020 Sb-124 l.16E-04 5.04E-04 1.74E-03 u AP 03 510636003 3/25/2020 Sb-125 3.31E-04 2.93E-04 l.02E-03 u AP 03 510636003 3/25/2020 Se-75 2.05E-04 1.59E-04 5.60E-04 u AP 03 510636003 3/25/2020 Th-228 8.35E-06 2.88E-04 9.46E-04 u AP 03 510636003 3/25/2020 Zn-65 -1.60E-04 2.96E-04 8.43E-04 u AP 03 510636003 3/25/2020 Zr-95 -7.82E-05 4.58E-04 l.45E-03 u AP 03 509289003 4/9/2020 BETA l.37E-02 8.94E-04 l.09E-03 AP 03 510087003 4/22/2020 BETA 2.74E-02 1.27E-03 l.02E-03 AP 03 510960003 51612020 BETA 1.75E-02 9.68E-04 1.08E-03 AP 03 511920003 5/20/2020 BETA 1.98E-02 9.84E-04 8.64E-04 AP 03 512893003 6/3/2020 BETA 1.66E-02 9.49E-04 1.09E-03 AP 03 514085003 6/17/2020 BETA 2.07E-02 l.07E-03 9.69E-04 AP 03 515124003 7/112020 BETA 2.36E-02 1.12E-03 9.41E-04 AP 03 517014003 7/l/2020 Ac-228 3.70E-04 4.90E-04 l.33E-03 u AP 03 517014003 7/112020 Ag-108m -1.29E-05 5.22E-05 l.68E-04 u AP 03 517014003 7/1/2020 Ag-llOm -1.49E-05 l.13E-04 3.78E-04 u AP 03 517014003 7/112020 Ba-140 1.58E-02 1.79E-02 6.13E-02 u AP 03 517014003 7/112020 Be-7 l.39E-01 9.36E-03 4.74E-03 AP 03 517014003 7/112020 Ce-141 3.87E-04 8.29E-04 1.28E-03 u AP 03 517014003 7/112020 Ce-144 -1.IOE-04 3.41E-04 1.04E-03 u AP 03 517014003 7/1/2020 Co-57 7.55E-05 4.78E-05 1.53E-04 u AP 03 517014003 7/1/2020 Co-58 2.0IE-04 1.77E-04 6.00E-04 u AP 03 517014003 7/112020 Co-60 -2.24E-05 8.05E-05 2.54E-04 u AP 03 517014003 7/1/2020 Cr-51 1.87E-03 4.14E-03 1.35E-02 u AP 03 517014003 7/112020 Cs-134 -2.71E-05 7.74E-05 2.34E-04 u AP 03 517014003 7/112020 Cs-137 -5. l IE-05 6.71E-05 l.94E-04 u AP 03 517014003 7/l/2020 Fe-59 3.75E-04 5.36E-04 l.89E-03 u AP 03 517014003 7/112020 I-131 O.OOE+OO 6.66E-02 O.OOE+OO UI AP 03 517014003 71112020 K-40 O.OOE+OO 1.63E-03 1.47E-03 u AP 03 517014003 7/1/2020 La-140 8.65E-03 8.27E-03 3.00E-02 u AP 03 517014003 7/112020 Mn-54 -2.08E-04 9.61E-05 2.12E-04 u AP 03 517014003 7/112020 Nb-95 -3.29E-04 2.08E-04 5.18E-04 u AP 03 517014003 7/112020 Ru-103 4.1 IE-05 2.13E-04 7.07E-04 u AP 03 517014003 7/112020 Ru-106 -3.27E-04 7.39E-04 2.28E-03 u AP 03 517014003 7/112020 Sb-124 -2.69E-05 5.lOE-04 1.64E-03 u AP 03 517014003 7/112020 Sb-125 1.68E-04 1.67E-04 5.74E-04 u AP 03 517014003 7/112020 Se-75 -1.58E-04 1.28E-04 3.87E-04 u AP 03 517014003 7/l/2020 Th-228 4.45E-04 2.78E-04 4.85E-04 u AP 03 517014003 7/l/2020 Zn-65 -1.28E-05 1.76E-04 5.08E-04 u 161

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/m3 ) (pCi/m3 ) (pCi/m3)

AP 03 517014003 71112020 Zr-95 1.15E-04 3.57E-04 l.05E-03 u AP 03 516358003 7/17/2020 BETA l.47E-02 8.70E-04 9.30E-04 AP 03 517178003 712912020 BETA 3.35E-02 l.53E-03 l.47E-03 AP 03 518829003 8112/2020 BETA 3.30E-02 1.32E-03 l.OIE-03 AP 03 519921003 8/26/2020 BETA 3.lOE-02 l.29E-03 9.95E-04 AP 03 521451003 91912020 BETA 2.29E-02 l.09E-03 9.03E-04 AP 03 522475003 912312020 BETA 2.26E-02 1.1 IE-03 9.69E-04 AP 03 526420003 9/23/2020 Ac-228 2.80E-04 4.96E-04 1.72E-03 u AP 03 526420003 912312020 Ag-108m 5.03E-05 8.00E-05 2.65E-04 u AP 03 526420003 912312020 Ag-llOm l.84E-05 l.56E-04 5.22E-04 u AP 03 526420003 9/23/2020 Ba-140 5.46E-02 3.99E-02 1.34E-01 u AP 03 526420003 912312020 Be-7 l.28E-01 8.69E-03 6.48E-03 AP 03 526420003 912312020 Ce-141 2.78E-04 7.0IE-04 2.21E-03 u AP 03 526420003 912312020 Ce-144 -l.62E-04 4.43E-04 1.48E-03 u AP 03 526420003 912312020 Co-57 l.85E-05 5.64E-05 l.95E-04 u AP 03 526420003 912312020 Co-58 2.40E-04 2.32E-04 7.91E-04 u AP 03 526420003 912312020 Co-60 -2.59E-06 1.19E-04 3.81E-04 u AP 03 526420003 912312020 Cr-51 -3.74E-03 6.03E-03 l.88E-02 u AP 03 526420003 912312020 Cs-134 l.76E-04 l.29E-04 4.28E-04 u AP 03 526420003 912312020 Cs-137 l.27E-04 9.36E-05 3.30E-04 u AP 03 526420003 9/23/2020 Fe-59 5.02E-04 5.38E-04 1.94E-03 u AP 03 526420003 912312020 1-131 O.OOE+OO l.76E-01 O.OOE+OO UI AP 03 526420003 912312020 K-40 5.63E-03 l.72E-03 2.55E-03 AP 03 526420003 912312020 La-140 -8.93E-03 l.41E-02 4.23E-02 u AP 03 526420003 912312020 Mn-54 -l.69E-04 l.08E-04 2.78E-04 u AP 03 526420003 912312020 Nb-95 3.44E-04 2.41E-04 8.46E-04 u AP 03 526420003 9/23/2020 Ru-103 -l.20E-04 3.53E-04 l.09E-03 u AP 03 526420003 912312020 Ru-106 5.26E-05 8.78E-04 2.98E-03 u AP 03 526420003 912312020 Sb-124 9.17E-04 5.80E-04 2.24E-03 u AP 03 526420003 912312020 Sb-125 2.37E-04 2.48E-04 7.53E-04 u AP 03 526420003 912312020 Se-75 -4.90E-05 l.74E-04 5.65E-04 u AP 03 526420003 9/23/2020 Th-228 O.OOE+OO 2.41E-04 5.86E-04 u AP 03 526420003 912312020 Zn-65 -3.06E-04 3.30E-04 9.56E-04 u AP 03 526420003 912312020 Zr-95 -6.87E-04 4.08E-04 l.03E-03 u AP 03 523935003 1017/2020 BETA 3.25E-02 1.32E-03 9.76E-04 AP 03 525295003 10/21/2020 BETA 2.66E-02 1. I 8E-03 9.74E-04 AP 03 527529003 11/6/2020 BETA 2.31E-02 l.02E-03 7.99E-04 AP 03 528278003 11/18/2020 BETA 3.98E-02 l.58E-03 1.23E-03 AP 03 529289003 12/2/2020 BETA 2.52E-02 1.16E-03 9.76E-04 AP 03 530489003 12/16/2020 BETA 2.49E-02 1.15E-03 9.25E-04 AP 03 531226003 12/30/2020 BETA 2.40E-02 1.17E-03 l.OOE-03 AP 03 533257003 12/30/2020 Ac-228 5.82E-04 5.94E-04 l.70E-03 u AP 03 533257003 12/30/2020 Ag-108m 6.64E-05 6.93E-05 2.37E-04 u AP 03 533257003 12/30/2020 Ag-I !Om 2.32E-04 2.0IE-04 7.08E-04 u AP 03 533257003 12/30/2020 Ba-140 5.40E-02 3.23E-02 7.35E-02 u AP 03 533257003 12/30/2020 Be-7 9.40E-02 7.86E-03 5.58E-03 162

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/m 3) (pCi/m3 ) (pCi/m3 )

AP 03 533257003 12/30/2020 Ce-141 1.41E-04 4.48E-04 l.42E-03 u AP 03 533257003 12/30/2020 Ce-144 8.69E-05 3.96E-04 1.16E-03 u AP 03 533257003 12/30/2020 Co-57 3.48E-05 4.67E-05 1.51E-04 u AP 03 533257003 12/30/2020 Co-58 1.59E-04 2.19E-04 7.26E-04 u AP 03 533257003 12/30/2020 Co-60 2.06E-05 9.87E-05 3.29E-04 u AP 03 533257003 12/30/2020 Cr-51 2.00E-03 3.80E-03 1.29E-02 u AP 03 533257003 12/30/2020 Cs-134 1.70E-04 1.14E-04 4.lOE-04 u AP 03 533257003 12/30/2020 Cs-137 -1.63E-04 9.69E-05 2.50E-04 u AP 03 533257003 12/30/2020 Fe-59 -1.02E-03 7.41E-04 l.80E-03 u AP 03 533257003 12/30/2020 1-131 3.95E-02 5.90E-02 2.0IE-01 u AP 03 533257003 12/30/2020 K-40 O.OOE+OO 1.60E-03 3.lOE-03 u AP 03 533257003 12/30/2020 La-140 -6.84E-03 9.15E-03 2.70E-02 u AP 03 533257003 12/30/2020 Mn-54 l.34E-04 l.31E-04 4.63E-04 u AP 03 533257003 12/30/2020 Nb-95 -3.38E-04 2.32E-04 6.27E-04 u AP 03 533257003 12/30/2020 Ru-103 3.70E-04 2.88E-04 9.94E-04 u AP 03 533257003 12/30/2020 Ru-106 -1.42E-04 9.24E-04 2.54E-03 u AP 03 533257003 12/30/2020 Sb-124 -4.28E-04 6.48E-04 1.92E-03 u AP 03 533257003 12/30/2020 Sb-125 1.29E-04 2.25E-04 7.59E-04 u AP 03 533257003 12/30/2020 Se-75 2.38E-05 l.31E-04 4.44E-04 u AP 03 533257003 12/30/2020 Th-228 2.0IE-04 1.71E-04 3.60E-04 u AP 03 533257003 12/30/2020 Zn-65 -3.32E-04 3.29E-04 7.45E-04 u AP 03 533257003 12/30/2020 Zr-95 -9.74E-05 3.69E-04 1.21E-03 u AP 04 501552004 1/15/2020 BETA 1.97E-02 9.92E-04 9.21E-04 AP 04 502825004 1/29/2020 BETA 3.03E-02 l.36E-03 1.lOE-03 AP 04 504483004 2/12/2020 BETA 2.55E-02 l. l 7E-03 1.0IE-03 AP 04 505599004 2/26/2020 BETA 3.60E-02 l.39E-03 9.72E-04 AP 04 506904004 3/11/2020 BETA 2.64E-02 l.17E-03 9.08E-04 AP 04 508060004 3/25/2020 BETA 2.89E-02 1.22E-03 9.16E-04 AP 04 510636004 3/25/2020 Ac-228 4.22E-04 4.95E-04 l.68E-03 u AP 04 510636004 3/25/2020 Ag-108m -2.23E-05 8.73E-05 2.73E-04 u AP 04 510636004 3/25/2020 Ag-1 !0m 3.16E-06 l.45E-04 4.74E-04 u AP 04 510636004 3/25/2020 Ba-140 -2.20E-02 3.59E-02 1.15E-Ol u AP 04 510636004 312512020 Be-7 l.32E-01 1.04E-02 6.33E-03 AP 04 510636004 3/25/2020 Ce-141 7.35E-05 6.28E-04 2.15E-03 u AP 04 510636004 312512020 Ce-144 -9.95E-04 5.86E-04 1.69E-03 u AP 04 510636004 3/25/2020 Co-57 -l.55E-04 8.03E-05 2.24E-04 u AP 04 510636004 312512020 Co-58 -2.27E-04 2.17E-04 6.06E-04 u AP 04 510636004 3/25/2020 Co-60 9.49E-05 1.27E-04 4.58E-04 u AP 04 510636004 3/25/2020 Cr-51 -9.37E-03 6.98E-03 1.98E-02 u AP 04 510636004 3/25/2020 Cs-134 9.80E-05 1.52E-04 5.22E-04 u AP 04 510636004 3/25/2020 Cs-137 -2.58E-05 9.39E-05 3.05E-04 u AP 04 510636004 3/25/2020 Fe-59 6.16E-04 7.70E-04 2.68E-03 u AP 04 510636004 312512020 1-131 -2.59E-02 1.50E-Ol O.OOE+OO u AP 04 510636004 3/25/2020 K-40 1.IOE-03 l.37E-03 4.84E-03 u AP 04 510636004 3/25/2020 La-140 -1.22E-02 1.28E-02 3.39E-02 u AP 04 510636004 3/25/2020 Mn-54 -1.17E-04 l.28E-04 3.70E-04 u AP 04 510636004 3/25/2020 Nb-95 4.53E-05 2.33E-04 7.84E-04 u AP 04 510636004 3/25/2020 Ru-103 -2.49E-04 4.29E-04 l.28E-03 u AP 04 510636004 3/25/2020 Ru-106 -5.84E-04 l.18E-03 3.80E-03 u 163

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/m3) (pCi/m3) (pCi/m3)

AP 04 510636004 3/25/2020 Sb-124 -8.61E-04 6.78E-04 1.55E-03 u AP 04 510636004 3/25/2020 Sb-125 2.77E-04 2.51E-04 8.50E-04 u AP 04 510636004 3/25/2020 Se-75 -2.76E-04 l.89E-04 5.34E-04 u AP 04 510636004 3/25/2020 Th-228 -l.09E-04 2.00E-04 6.32E-04 u AP 04 510636004 3/25/2020 Zn-65 2.llE-04 3.44E-04 1.17E-03 u AP 04 510636004 3/25/2020 Zr-95 9.37E-05 3.87E-04 1.31E-03 u AP 04 509289004 4/9/2020 BETA l.51E-02 7.95E-04 7.35E-04 AP 04 510087004 4/22/2020 BETA 2.llE-02 1.03E-03 9.03E-04 AP 04 510960004 5/6/2020 BETA l.75E-02 8.95E-04 8.18E-04 AP 04 511920004 5/20/2020 BETA l.80E-02 9.30E-04 8.30E-04 AP 04 512893004 6/3/2020 BETA l.51E-02 8.86E-04 9.22E-04 AP 04 514085004 6/17/2020 BETA l.91E-02 9.80E-04 8.99E-04 AP 04 515124004 7/1/2020 BETA 2.24E-02 l.06E-03 9.0lE-04 AP 04 517014004 7/1/2020 Ac-228 1.44E-04 4.16E-04 l.24E-03 u AP 04 517014004 7/1/2020 Ag-108m 7.86E-05 4.99E-05 l.74E-04 u AP 04 517014004 7/1/2020 Ag-llOm -l.19E-04 l.05E-04 2.81E-04 u AP 04 517014004 7/1/2020 Ba-140 -3.56E-02 l.95E-02 4.91E-02 u AP 04 517014004 7/1/2020 Be-7 1.33E-01 8.19E-03 4.72E-03 AP 04 517014004 7/1/2020 Ce-141 -6.92E-04 4.57E-04 1.26E-03 u AP 04 517014004 7/1/2020 Ce-144 -l.89E-04 3.76E-04 1. l 7E-03 u AP 04 517014004 7/1/2020 Co-57 2.31E-05 4.54E-05 l.49E-04 u AP 04 517014004 7/1/2020 Co-58 -l.79E-04 1.57E-04 3.63E-04 u AP 04 517014004 7/1/2020 Co-60 3.62E-05 8.75E-05 3.08E-04 u AP 04 517014004 7/112020 Cr-51 -3.55E-03 3.53E-03 1.12E-02 u AP 04 517014004 7/112020 Cs-134 -2.58E-05 6.73E-05 2.09E-04 u AP 04 517014004 7/1/2020 Cs-137 -6.72E-05 7.24E-05 2.15E-04 u AP 04 517014004 7/112020 Fe-59 2.69E-04 5.78E-04 l.92E-03 u AP 04 517014004 7/1/2020 1-131 -1.18E-01 6.53E-02 O.OOE+OO u AP 04 517014004 7/1/2020 K-40 O.OOE+OO l.58E-03 l.99E-03 u AP 04 517014004 7/1/2020 La-140 -l.68E-03 7.12E-03 2.30E-02 u AP 04 517014004 7/1/2020 Mn-54 5.79E-05 8.02E-05 2.75E-04 u AP 04 517014004 7/1/2020 Nb-95 -5.68E-05 l.60E-04 5.06E-04 u AP 04 517014004 7/1/2020 Ru-103 l.16E-04 2.34E-04 8.05E-04 u AP 04 517014004 7/1/2020 Ru-106 l.76E-03 7.57E-04 2.52E-03 u AP 04 517014004 7/1/2020 Sb-124 -6.55E-05 4.18E-04 1.36E-03 u AP 04 517014004 7/112020 Sb-125 -6.05E-05 l.48E-04 4.83E-04 u AP 04 517014004 7/112020 Se-75 8.30E-05 1.35E-04 4.32E-04 u AP 04 517014004 7/1/2020 Th-228 l.71E-04 l.78E-04 4.32E-04 u AP 04 517014004 7/1/2020 Zn-65 -1.30E-04 l.90E-04 5.43E-04 u AP 04 517014004 7/1/2020 Zr-95 3.14E-04 2.91E-04 1.0lE-03 u AP 04 516358004 7/17/2020 BETA l.76E-02 9.26E-04 8.40E-04 AP 04 517178004 7/29/2020 BETA 3.54E-02 l.55E-03 l.24E-03 AP 04 518829004 8/12/2020 BETA 3.07E-02 l.28E-03 l.OOE-03 AP 04 519921004 8/26/2020 BETA 2.70E-02 l.23E-03 l.OlE-03 AP 04 521451004 9/9/2020 BETA 2.21E-02 1.15E-03 l.18E-03 AP 04 522475004 9/23/2020 BETA 2.02E-02 1.18E-03 l.22E-03 164

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/m3 ) (pCi/m3 ) (pCi/m3 )

AP 04 526420004 9/23/2020 Ac-228 -2.70E-05 5.15E-04 l.63E-03 u AP 04 526420004 9/23/2020 Ag- I 08m -l.99E-04 8.23E-05 l.69E-04 u AP 04 526420004 9/23/2020 Ag-I !Om l.29E-05 l.82E-04 6.05E-04 u AP 04 526420004 9/23/2020 Ba-140 2.20E-02 4.93E-02 l.46E-01 u AP 04 526420004 9/23/2020 Be-7 l.18E-Ol 9.87E-03 7.83E-03 AP 04 526420004 9/23/2020 Ce-141 -l.05E-03 7.70E-04 2.00E-03 u AP 04 526420004 9/23/2020 Ce-144 5.26E-05 4.93E-04 l.57E-03 u AP 04 526420004 9/23/2020 Co-57 -6.69E-05 6.51E-05 l.91E-04 u AP 04 526420004 9/23/2020 Co-58 3.99E-05 2.14E-04 7.26E-04 u AP 04 526420004 9/23/2020 Co-60 l.58E-04 l.46E-04 4.76E-04 u AP 04 526420004 9/23/2020 Cr-51 4.19E-03 6.19E-03 2.llE-02 u AP 04 526420004 9/23/2020 Cs-134 l.44E-04 l.18E-04 4.15E-04 u AP 04 526420004 9/23/2020 Cs-137 l.63E-05 9.30E-05 3.19E-04 u AP 04 526420004 9/23/2020 Fe-59 -l.20E-03 6.13E-04 5.68E-04 u AP 04 526420004 9/23/2020 I-131 -2.52E-Ol 2.25E-Ol O.OOE+OO u AP 04 526420004 9/23/2020 K-40 6.IOE-04 2.15E-03 7.34E-03 u AP 04 526420004 9/23/2020 La-140 -7.66E-03 2.IOE-02 5.67E-02 u AP 04 526420004 9/23/2020 Mn-54 -2.33E-04 l.45E-04 3.90E-04 u AP 04 526420004 9/23/2020 Nb-95 -2.04E-05 2.72E-04 8.46E-04 u AP 04 526420004 9/23/2020 Ru-103 -4.54E-04 4.06E-04 l.15E-03 u AP 04 526420004 9/23/2020 Ru-106 -l.72E-03 l.15E-03 2.43E-03 u AP 04 526420004 9/23/2020 Sb-124 -3.68E-04 6.35E-04 l.90E-03 u AP 04 526420004 9/23/2020 Sb-125 l.92E-04 2.33E-04 7.89E-04 u AP 04 526420004 9/23/2020 Se-75 l.92E-05 l.58E-04 5.37E-04 u AP 04 526420004 9/23/2020 Th-228 O.OOE+OO 3.78E-04 6.39E-04 u AP 04 526420004 9/23/2020 Zn-65 -6.90E-04 3.36E-04 7.0IE-04 u AP 04 526420004 9/23/2020 Zr-95 8.41E-05 4.18E-04 l.42E-03 u AP 04 523935004 1017/2020 BETA 3.70E-02 l.55E-03 l.15E-03 AP 04 525295004 10/21/2020 BETA 3.13E-02 l.47E-03 l.21E-03 AP 04 527529004 11/6/2020 BETA 2.70E-02 l.05E-03 6.98E-04 AP 04 528278004 11/18/2020 BETA 5.74E-02 l.80E-03 l.06E-03 AP 04 529289004 12/2/2020 BETA 3.02E-02 l.18E-03 8.32E-04 AP 04 530489004 12/16/2020 BETA 2.56E-02 l.1 IE-03 8.63E-04 AP 04 531226004 12/30/2020 BETA 3.04E-02 l.20E-03 9.02E-04 AP 04 533257004 12/30/2020 Ac-228 1.23E-03 5.04E-04 l.66E-03 u AP 04 533257004 12/30/2020 Ag-108m -9.18E-05 6.35E-05 l.73E-04 u AP 04 533257004 12/30/2020 Ag-11 Om -2.08E-05 l.27E-04 3.67E-04 u AP 04 533257004 12/30/2020 Ba-140 l.5IE-02 l.92E-02 6.49E-02 u AP 04 533257004 12/30/2020 Be-7 l.18E-Ol 8.51E-03 5.15E-03 AP 04 533257004 12/30/2020 Ce-141 -l.86E-04 3.74E-04 l.13E-03 u AP 04 533257004 12/30/2020 Ce-144 -3.73E-04 3.39E-04 9.51E-04 u AP 04 533257004 12/30/2020 Co-57 -l.06E-04 5.56E-05 l.26E-04 u AP 04 533257004 12/30/2020 Co-58 5.82E-05 l.51E-04 5.28E-04 u AP 04 533257004 12/30/2020 Co-60 l.05E-04 9.29E-05 3.40E-04 u AP 04 533257004 12/30/2020 Cr-51 l.15E-03 3.26E-03 l.l IE-02 u AP 04 533257004 12/30/2020 Cs-134 2.55E-05 9.42E-05 3.27E-04 u AP 04 533257004 12/30/2020 Cs-137 -7.78E-05 8.28E-05 2.33E-04 u AP 04 533257004 12/30/2020 Fe-59 4.03E-04 5.33E-04 l.89E-03 u AP 04 533257004 12/30/2020 I-131 -2.15E-02 5.59E-02 l.81E-Ol u 165

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV.* MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/m3) (pCi/m3) (pCi/m3)

AP 04 533257004 12/30/2020 K-40 4.0IE-04 2.03E-03 l.53E-03 u AP 04 533257004 12/30/2020 La-140 -9.80E-03 8.07E-03 1.98E-02 u AP 04 533257004 12/30/2020 Mn-54 -4.94E-05 9.69E-05 3.IIE-04 u AP 04 533257004 12/30/2020 Nb-95 2.15E-04 1.91£-04 6.50E-04 u AP 04 533257004 12/30/2020 Ru-103 1.47E-04 2.60E-04 7.98E-04 u AP 04 533257004 12/30/2020 Ru-106 -1.07E-03 8.71£-04 2.36E-03 u AP 04 533257004 12/30/2020 Sb-124 8.32E-04 4.76E-04 1.86E-03 u AP 04 533257004 12/30/2020 Sb-125 -3.81£-04 2.20E-04 5.69E-04 u AP 04 533257004 12/30/2020 Se-75 -1.53E-04 1.26E-04 3.80E-04 u AP 04 533257004 12/30/2020 Th-228 O.OOE+OO 2.08E-04 3.50E-04 u AP 04 533257004 12/30/2020 Zn-65 -1.56E-04 2.42E-04 7.38E-04 u AP 04 533257004 12/30/2020 Zr-95 3.20E-04 2.94E-04 1.02E-03 u AP 05 501552005 1/15/2020 BETA 2.38E-02 1.21£-03 1.15E-03 AP 05 502825005 1/29/2020 BETA 2.26E-02 1.13E-03 1.05E-03 AP 05 504483005 2/12/2020 BETA 2.24E-02 l.16E-03 1.06E-03 AP 05 505599005 2/26/2020 BETA 3.97E-02 1.67E-03 1.27E-03 AP 05 506904005 3/11/2020 BETA 2.40E-02 1.25E-03 l.14E-03 AP 05 508060015 3/30/2020 BETA 2.62E-02 1.20E-03 9.75E-04 AP 05 510636008 3/30/2020 Ac-228 -6.70E-04 5.47E-04 1.62E-03 u AP 05 510636008 3/30/2020 Ag-108m 1.26E-05 7.45E-05 2.49E-04 u AP 05 510636008 3/30/2020 Ag-llOm -1.69E-04 1.73E-04 4.25E-04 u AP 05 510636008 3/30/2020 Ba-140 1. IOE-02 2.73E-02 9.15E-02 u AP 05 510636008 3/30/2020 Be-7 1.09E-01 8.98E-03 6.87E-03 AP 05 510636008 3/30/2020 Ce-141 -3.56E-04 6.44E-04 1.91£-03 u AP 05 510636008 3/30/2020 Ce-144 1.53E-04 4.38E-04 1.43E-03 u AP 05 510636008 3/30/2020 Co-57 -5.69E-05 6.32E-05 1.89E-04 u AP 05 510636008 3/30/2020 Co-58 2.58E-04 1.90E-04 6.91£-04 u AP 05 510636008 3/30/2020 Co-60 1.64E-04 1.25E-04 4.51£-04 u AP 05 510636008 3/30/2020 Cr-51 -2.52E-04 4.87E-03 1.64E-02 u AP 05 510636008 3/30/2020 Cs-134 2.08E-04 1.16E-04 4.16E-04 u AP 05 510636008 3/30/2020 Cs-137 7.18E-05 9.50E-05 3.22E-04 u AP 05 510636008 3/30/2020 Fe-59 1.19E-04 7.53E-04 2.62E-03 u AP 05 510636008 3/30/2020 I-131 -8.52E-02 9.68E-02 0.00E+OO u AP 05 510636008 3/30/2020 K-40 O.OOE+OO 2.20E-03 3.15E-03 u AP 05 510636008 3/30/2020 La-140 -1.87E-02 1.22E-02 2.56E-02 u AP 05 510636008 3/30/2020 Mn-54 -1.60E-04 1.25E-04 3.57E-04 u AP 05 510636008 3/30/2020 Nb-95 -6.32E-05 3.09E-04 8.28E-04 u AP 05 510636008 3/30/2020 Ru-103 -1.64E-04 3.12E-04 9.71£-04 u AP 05 510636008 3/30/2020 Ru-106 -7.14E-04 9.95E-04 2.96E-03 u AP 05 510636008 3/30/2020 Sb-124 -4.79E-04 5.39E-04 1.50E-03 u AP 05 510636008 3/30/2020 Sb-125 -1.82E-04 2.04E-04 6.12E-04 u AP 05 510636008 3/30/2020 Se-75 5.23E-04 2.15E-04 5.88E-04 u AP 05 510636008 3/30/2020 Th-228 1.38E-04 2.74E-04 4.39E-04 u AP 05 510636008 3/30/2020 Zn-65 1.82E-04 2.87E-04 1.00E-03 u AP 05 510636008 3/30/2020 Zr-95 2.1 IE-04 3.28E-04 1.IIE-03 u AP 05 509289005 4/9/2020 BETA l.1 IE-02 9.05E-04 1.22E-03 AP 05 510087005 4/22/2020 BETA 2.91£-02 1.31£-03 1.05E-03 166

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/m3) (pCi/m 3 ) (pCi/m3 )

AP 05 510960005 51612020 BETA l.63E-02 8.98E-04 8.82E-04 AP 05 511920005 5/20/2020 BETA l.90E-02 9.94E-04 8.97E-04 AP 05 512893005 6/3/2020 BETA l.73E-02 9.52E-04 9.50E-04 AP 05 514085005 611712020 BETA 2.31E-02 l.08E-03 9.03E-04 AP 05 515124005 71112020 BETA 2.16E-02 l.IOE-03 l.13E-03 AP 05 517014005 71112020 Ac-228 3.93E-05 4.67E-04 l.22E-03 u AP 05 517014005 71112020 Ag-108m -2.54E-05 4.95E-05 l.60E-04 u AP 05 517014005 71112020 Ag-llOm 6.52E-05 9.98E-05 3.45E-04 u AP 05 517014005 71112020 Ba-140 -3.66E-02 l.84E-02 4.19E-02 u AP 05 517014005 71112020 Be-7 l.23E-Ol 8.25E-03 4.60E-03 AP 05 517014005 71112020 Ce-141 2.69E-04 4.77E-04 l.09E-03 u AP 05 517014005 71112020 Ce-144 -7.42E-06 2.94E-04 9.53E-04 u AP 05 517014005 71112020 Co-57 6.59E-05 4.40E-05 l.46E-04 u AP 05 517014005 71112020 Co-58 -l.69E-04 l.43E-04 3.80E-04 u AP 05 517014005 71112020 Co-60 -7.13E-05 9.06E-05 2.71E-04 u AP 05 517014005 71112020 Cr-51 1.SIE-04 3.15E-03 l.09E-02 u AP 05 517014005 71112020 Cs-134 7.31E-05 9.06E-05 2.46E-04 u AP 05 517014005 71112020 Cs-137 3.42E-05 5.45E-05 l.90E-04 u AP 05 517014005 71112020 Fe-59 l.17E-04 4.52E-04 l.48E-03 u AP 05 517014005 71112020 I-131 O.OOE+OO 6.36E-02 O.OOE+OO UI AP 05 517014005 71112020 K-40 O.OOE+OO l.50E-03 2.97E-03 u AP 05 517014005 71112020 La-140 7.68E-04 7.IOE-03 2.39E-02 u AP 05 517014005 71112020 Mn-54 -l.45E-04 9.76E-05 l.97E-04 u AP 05 517014005 71112020 Nb-95 -l.36E-04 l.46E-04 4.14E-04 u AP 05 517014005 71112020 Ru-103 -2.0IE-04 2.45E-04 6.54E-04 u AP 05 517014005 71112020 Ru-106 -6.76E-06 7.07E-04 2.34E-03 u AP 05 517014005 71112020 Sb-124 -5.54E-04 4.59E-04 l.13E-03 u AP 05 517014005 71112020 Sb-125 -9.2IE-06 l.44E-04 4.84E-04 u AP 05 517014005 71112020 Se-75 l.17E-04 l.26E-04 3.82E-04 u AP 05 517014005 71112020 Th-228 9.29E-05 2.0IE-04 4.51E-04 u AP 05 517014005 7/l/2020 Zn-65 -4.57E-07 2.37E-04 7.49E-04 u AP 05 517014005 71112020 Zr-95 2.82E-04 2.84E-04 9.90E-04 u AP 05 516358005 7/17/2020 BETA l.50E-02 8.79E-04 8.86E-04 AP 05 517178005 7/29/2020 BETA 3.25E-02 l.5IE-03 l.29E-03 AP 05 518829005 8/12/2020 BETA 2.92E-02 l.23E-03 9.98E-04 AP 05 519921005 8/26/2020 BETA 2.63E-02 1.15E-03 9.09E-04 AP 05 521451005 9/9/2020 BETA 2.15E-02 l.08E-03 9.58E-04 AP 05 522475005 9/23/2020 BETA l.94E-02 9.92E-04 8.85E-04 AP 05 526420005 9/23/2020 Ac-228 -4.24E-04 9.l IE-04 2.62E-03 u AP 05 526420005 9/23/2020 Ag-108m -5.88E-05 l.44E-04 4.lOE-04 u AP 05 526420005 9/23/2020 Ag-1 lOm 5.05E-04 3.24E-04 l.13E-03 u AP 05 526420005 9/23/2020 Ba-140 8.89E-02 8.16E-02 2.84E-Ol u AP 05 526420005 9/23/2020 Be-7 l.09E-Ol l.17E-02 8.90E-03 AP 05 526420005 9/23/2020 Ce-141 2.96E-04 8.9IE-04 2.78E-03 u AP 05 526420005 9/23/2020 Ce-144 4.89E-04 7.61E-04 2.57E-03 u AP 05 526420005 9/23/2020 Co-57 3.l IE-05 8.78E-05 2.97E-04 u AP 05 526420005 9/23/2020 Co-58 l.26E-04 3.59E-04 l.20E-03 u 167

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/m3) (pCi/m3) (pCi/m3 )

AP 05 526420005 9/23/2020 Co-60 5.26E-05 2.12E-04 7.23E-04 u AP 05 526420005 9/23/2020 Cr-51 l.OlE-02 8.41E-03 2.81E-02 u AP 05 526420005 9/23/2020 Cs-134 -l.77E-04 2.06E-04 5.90E-04 u AP 05 526420005 9/23/2020 Cs-137 -2.96E-04 2.19E-04 5.06E-04 u AP 05 526420005 9/23/2020 Fe-59 2.13E-04 l.65E-03 5.02E-03 u AP 05 526420005 9/23/2020 1-131 O.OOE+OO 2.79E-01 0.00E+OO Ul AP 05 526420005 9/23/2020 K-40 5.15E-06 2.99E-03 6.41E-03 u AP 05 526420005 9/23/2020 La-140 -8.98E-02 4.13E-02 6.89E-02 u AP 05 526420005 9/23/2020 Mn-54 -2.19E-04 2.55E-04 6.66E-04 u AP 05 526420005 9/23/2020 Nb-95 4.35E-04 4.58E-04 l.58E-03 u AP 05 526420005 9/23/2020 Ru-103 7.34E-04 7.32E-04 2.56E-03 u AP 05 526420005 9/23/2020 Ru-106 7.70E-04 l.78E-03 6.05E-03 u AP 05 526420005 9/23/2020 Sb-124 3.22E-04 l.03E-03 3.54E-03 u AP 05 526420005 9/23/2020 Sb-125 -2.70E-04 3.73E-04 1.18E-03 u AP 05 526420005 9/23/2020 Se-75 3.84E-05 2.92E-04 9.35E-04 u AP 05 526420005 9/23/2020 Th-228 l.44E-05 2.68E-04 9.36E-04 u AP 05 526420005 9/23/2020 Zn-65 4.29E-04 4.50E-04 1.64E-03 u AP 05 526420005 9/23/2020 Zr-95 1.12E-03 8.23E-04 2.87E-03 u AP 05 523935005 101712020 BETA 3.21E-02 l.28E-03 9.05E-04 AP 05 525295005 10/21/2020 BETA 2.19E-02 l.09E-03 9.79E-04 AP 05 527529005 11/6/2020 BETA 2.21E-02 l.02E-03 8.39E-04 AP 05 528278005 11/18/2020 BETA 4.04E-02 l.58E-03 1.16E-03 AP 05 529289005 12/2/2020 BETA 2.50E-02 1.15E-03 9.85E-04 AP 05 530489005 12/16/2020 BETA 2.54E-02 1.17E-03 9.57E-04 AP 05 531226005 12/30/2020 BETA 2.30E-02 l.09E-03 8.96E-04 AP 05 533257005 12/30/2020 Ac-228 6.23E-04 4.80E-04 1.45E-03 u AP 05 533257005 12/30/2020 Ag-108m -5.25E-05 6.87E-05 2.02E-04 u AP 05 533257005 12/30/2020 Ag-1 lOm -4.29E-04 2.15E-04 3.23E-04 u AP 05 533257005 12/30/2020 Ba-140 -8.98E-03 l.69E-02 5.36E-02 u AP 05 533257005 12/30/2020 Be-7 9.17E-02 7.43E-03 5.34E-03 AP 05 533257005 12/30/2020 Ce-141 -4.36E-04 3.99E-04 l.25E-03 u AP 05 533257005 12/30/2020 Ce-144 7.93E-05 3.96E-04 l.25E-03 u AP 05 533257005 12/30/2020 Co-57 -2.62E-05 5.35E-05 l.61E-04 u AP 05 533257005 12/30/2020 Co-58 1.24E-04 l.64E-04 5.66E-04 u AP 05 533257005 12/30/2020 Co-60 -2.21E-04 1.30E-04 2.92E-04 u AP 05 533257005 12/30/2020 Cr-51 -3.86E-03 3.84E-03 1.13E-02 u AP 05 533257005 12/30/2020 Cs-134 -3.67E-06 8.32E-05 2.69E-04 u AP 05 533257005 12/30/2020 Cs-137 -6.13E-05 8.60E-05 2.60E-04 u AP 05 533257005 12/30/2020 Fe-59 1.38E-04 4.95E-04 l.71E-03 u AP 05 533257005 12/30/2020 1-131 -3.58E-02 5.67E-02 l.72E-01 u AP 05 533257005 12/30/2020 K-40 5.42E-04 1.57E-03 l.85E-03 u AP 05 533257005 12/30/2020 La-140 -3.58E-03 8.04E-03 2.39E-02 u AP 05 533257005 12/30/2020 Mn-54 l.91E-05 l.06E-04 3.38E-04 u AP 05 533257005 12/30/2020 Nb-95 2.40E-04 l.86E-04 6.09E-04 u AP 05 533257005 12/30/2020 Ru-103 3.54E-04 2.74E-04 9.64E-04 u AP 05 533257005 12/30/2020 Ru-106 3.79E-04 9.46E-04 3.22E-03 u AP 05 533257005 12/30/2020 Sb-124 1.27E-04 4.83E-04 1.69E-03 u AP 05 533257005 12/30/2020 Sb-125 2.17E-04 2.14E-04 7.15E-04 u AP 05 533257005 12/30/2020 Se-75 2.44E-05 l.24E-04 4.14E-04 u 168

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/m3 ) (pCi/m 3 ) (pCi/m 3 )

AP 05 533257005 12/30/2020 Th-228 2.73E-04 l.91E-04 4.77E-04 u AP 05 533257005 12/30/2020 Zn-65 -l.14E-04 2.14E-04 6.60E-04 u AP 05 533257005 12/30/2020 Zr-95 6.20E-05 2.90E-04 9.68E-04 u AP 07 501552006 1/15/2020 BETA 2.48E-02 9.98E-04 7.48E-04 AP 07 502825006 1/29/2020 BETA 2.27E-02 9.61E-04 7.67E-04 AP 07 504483006 2/12/2020 BETA 2.89E-02 l.22E-03 9.62E-04 AP 07 505599006 2/26/2020 BETA 3.58E-02 l.22E-03 7.65E-04 AP 07 506904006 3/11/2020 BETA 2.29E-02 9.80E-04 7.53E-04 AP 07 508060005 3/25/2020 BETA 2.56E-02 l.06E-03 9.0IE-04 AP 07 510636005 3/25/2020 Ac-228 3.62E-04 4.61E-04 l.43E-03 u AP 07 510636005 3/25/2020 Ag-108m l.33E-05 6.05E-05 2.05E-04 u AP 07 510636005 3/25/2020 Ag-11 Om -l.19E-04 9.04E-05 2.34E-04 u AP 07 510636005 3/25/2020 Ba-140 2.30E-03 l.85E-02 6.15E-02 u AP 07 510636005 3/25/2020 Be-7 l.40E-Ol 9.18E-03 5.81E-03 AP 07 510636005 3/25/2020 Ce-141 -l.72E-04 4.34E-04 l.26E-03 u AP 07 510636005 3/25/2020 Ce-144 -2.87E-04 3.74E-04 l.15E-03 u AP 07 510636005 3/25/2020 Co-57 3.0IE-05 4.66E-05 l.56E-04 u AP 07 510636005 3/25/2020 Co-58 7.14E-05 l.26E-04 4.29E-04 u AP 07 510636005 3/25/2020 Co-60 -6.25E-05 7.76E-05 2.17E-04 u AP 07 510636005 3/25/2020 Cr-51 -7.IOE-04 3.61E-03 l.22E-02 u AP 07 510636005 3/25/2020 Cs-134 -l.58E-04 9.51E-05 2.20E-04 u AP 07 510636005 3/25/2020 Cs-137 l.17E-04 l.2IE-04 2.42E-04 u AP 07 510636005 3/25/2020 Fe-59 -5.36E-04 5.73E-04 l.67E-03 u AP 07 510636005 3/25/2020 I-131 -3.12E-02 8.13E-02 O.OOE+OO u AP 07 510636005 3/25/2020 K-40 2.57E-03 l.92E-03 2.67E-03 u AP 07 510636005 3/25/2020 La-140 -l.13E-03 8.09E-03 2.54E-02 u AP 07 510636005 3/25/2020 Mn-54 O.OOE+OO O.OOE+OO 2.83E-04 u AP 07 510636005 3/25/2020 Nb-95 -4.34E-05 2.29E-04 6.82E-04 u AP 07 510636005 3/25/2020 Ru-103 5.0IE-05 2.72E-04 9.13E-04 u AP 07 510636005 3/25/2020 Ru-106 6.74E-05 7.76E-04 2.43E-03 u AP 07 510636005 3/25/2020 Sb-124 -l.17E-03 5.98E-04 9.7IE-04 u AP 07 510636005 3/25/2020 Sb-125 -l.06E-04 l.74E-04 5.5IE-04 u AP 07 510636005 3/25/2020 Se-75 5.90E-05 l.26E-04 4.03E-04 u AP 07 510636005 3/25/2020 Th-228 l.75E-04 l.67E-04 3.45E-04 u AP 07 510636005 3/25/2020 Zn-65 l.02E-05 2.19E-04 7.33E-04 u AP 07 510636005 3/25/2020 Zr-95 8.74E-05 3.25E-04 9.59E-04 u AP 07 509289006 4/9/2020 BETA l.87E-02 l.OOE-03 9.30E-04 AP 07 510087006 4/22/2020 BETA 2.35E-02 l.13E-03 l.06E-03 AP 07 510960006 5/6/2020 BETA 2.26E-02 l.16E-03 9.87E-04 AP 07 511920006 5/20/2020 BETA l.63E-02 9.3IE-04 9.28E-04 AP 07 512893006 6/3/2020 BETA l.79E-02 9.78E-04 9.73E-04 AP 07 514085006 6/17/2020 BETA 2.03E-02 l.09E-03 l.14E-03 AP 07 515124006 7/1/2020 BETA 2.59E-02 l.25E-03 l.l IE-03 AP 07 517014006 7/1/2020 Ac-228 -1.17E-03 6.07E-04 l.39E-03 u AP 07 517014006 7/1/2020 Ag-108m -3.96E-05 7.57E-05 2.04E-04 u AP 07 517014006 7/1/2020 Ag-llOm -6.60E-05 l.52E-04 4.78E-04 u 169

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/m3 ) (pCi/m3) (pCi/m3 )

AP 07 517014006 7/1/2020 Ba-140 4.55E-02 2.90E-02 9.0IE-02 u AP 07 517014006 711/2020 Be-7 1.34E-01 9.76E-03 7.45E-03 AP 07 517014006 7/1/2020 Ce-141 -2.55E-04 4.60E-04 1.53E-03 u AP 07 517014006 7/1/2020 Ce-144 4.67E-05 3.71E-04 1.16E-03 u AP 07 517014006 7/1/2020 Co-57 -4.29E-06 4.88E-05 1.52E-04 u AP 07 517014006 7/1/2020 Co-58 1.67E-05 1.95E-04 6.57E-04 u AP 07 517014006 7/1/2020 Co-60 1.43E-04 1.21E-04 4.35E-04 u AP 07 517014006 7/1/2020 Cr-51 1.50E-03 4.66E-03 1.56E-02 u AP 07 517014006 7/1/2020 Cs-134 7.llE-05 1.24E-04 3.91E-04 u AP 07 517014006 7/1/2020 Cs-137 -1.17E-04 1.26E-04 3.30E-04 u AP 07 517014006 7/1/2020 Fe-59 6.31E-04 4.19E-04 1.66E-03 u AP 07 517014006 7/1/2020 I-131 -2.39E-02 8.53E-02 O.OOE+OO u AP 07 517014006 7/1/2020 K-40 1.79E-03 l.73E-03 6.22E-03 u AP 07 517014006 7/1/2020 La-140 -2.08E-03 9.27E-03 2.99E-02 u AP 07 517014006 7/1/2020 Mn-54 -5.12E-05 1.07E-04 3.37E-04 u AP 07 517014006 7/1/2020 Nb-95 -5.88E-04 2.72E-04 5.51E-04 u AP 07 517014006 7/1/2020 Ru-103 -4.06E-04 3.14E-04 8.28E-04 u AP 07 517014006 7/1/2020 Ru-106 -2.72E-04 8.39E-04 2.77E-03 u AP 07 517014006 7/1/2020 Sb-124 -3.73E-04 3.99E-04 9.43E-04 u AP 07 517014006 7/1/2020 Sb-125 8.39E-05 2.45E-04 8.12E-04 u AP 07 517014006 7/1/2020 Se-75 -9.97E-05 1.49E-04 4.75E-04 u AP 07 517014006 7/1/2020 Th-228 9.07E-05 1.67E-04 3.67E-04 u AP 07 517014006 7/1/2020 Zn-65 2.24E-04 2.44E-04 8.73E-04 u AP 07 517014006 7/1/2020 Zr-95 -1.93E-04 4.04E-04 1.29E-03 u AP 07 516358006 7/17/2020 BETA 1.37E-02 8.70E-04 9.22E-04 AP 07 517178006 7/29/2020 BETA 3.44E-02 1.55E-03 1.23E-03 AP 07 518829006 8/12/2020 BETA 3.36E-02 1.26E-03 9.95E-04 AP 07 519921006 8/26/2020 BETA 1.72E-02 9.22E-04 9.61E-04 AP 07 521451006 9/9/2020 BETA 1.92E-02 9.57E-04 8.67E-04 AP 07 522475006 9/23/2020 BETA 1.65E-02 9.05E-04 9.60E-04 AP 07 526420006 9/23/2020 Ac-228 9.63E-04 8.13E-04 1.84E-03 u AP 07 526420006 9/23/2020 Ag-108m 3.58E-06 6.80E-05 2.26E-04 u AP 07 526420006 9/23/2020 Ag-1 lOm -8.83E-05 1.81E-04 5.39E-04 u AP 07 526420006 9/23/2020 Ba-140 3.90E-02 3.61E-02 1.27E-01 u AP 07 526420006 9/23/2020 Be-7 1.18E-01 1.00E-02 7.31E-03 AP 07 526420006 9/23/2020 Ce-141 -8.76E-05 6.88E-04 1.98E-03 u AP 07 526420006 9/23/2020 Ce-144 5.75E-04 5.15E-04 1.68E-03 u AP 07 526420006 9/23/2020 Co-57 3.43E-05 6.96E-05 2.12E-04 u AP 07 526420006 9/23/2020 Co-58 -1.73E-04 2.IOE-04 5.87E-04 u AP 07 526420006 9/23/2020 Co-60 1.91E-04 1.30E-04 4.75E-04 u AP 07 526420006 9123/2020 Cr-51 -4.08E-03 6.73E-03 2.17E-02 u AP 07 526420006 9/23/2020 Cs-134 9.14E-05 l.09E-04 3.60E-04 u AP 07 526420006 9/23/2020 Cs-137 -1.27E-05 9.08E-05 2.89E-04 u AP 07 526420006 9/23/2020 Fe-59 -3.91E-04 7.07E-04 2.19E-03 u AP 07 526420006 9/23/2020 I-131 O.OOE+OO 2.02E-01 O.OOE+OO UI AP 07 526420006 9/23/2020 K-40 l.66E-03 2.08E-03 3.71E-03 u AP 07 526420006 9/23/2020 La-140 1.43E-02 1.71E-02 6.15E-02 u 170

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/m3 ) (pCi/m 3 ) (pCi/m3 )

AP 07 526420006 9/23/2020 Mn-54 2.80E-05 1.24E-04 4.02E-04 u AP 07 526420006 9/23/2020 Nb-95 -1.99E-04 3.35E-04 9.90E-04 u AP 07 526420006 9/23/2020 Ru-103 1.81E-04 3.72E-04 1.27E-03 u AP 07 526420006 9/23/2020 Ru-106 -4.21E-04 9.28E-04 2.87E-03 u AP 07 526420006 9/23/2020 Sb-124 5.83E-04 7.92E-04 2.80E-03 u AP 07 526420006 9/23/2020 Sb-125 -3.36E-04 2.75E-04 8.0IE-04 u AP 07 526420006 9/23/2020 Se-75 3.62E-05 1.59E-04 5.45E-04 u AP 07 526420006 9/23/2020 Th-228 1.0IE-04 2.37E-04 6.22E-04 u AP 07 526420006 9/23/2020 Zn-65 9.78E-05 2.23E-04 7.87E-04 u AP 07 526420006 9/23/2020 Zr-95 1.84E-05 3.75E-04 1.21E-03 u AP 07 523935006 10/7/2020 BETA 3.38E-02 1.27E-03 9.17E-04 AP 07 525295006 10/21/2020 BETA 2.66E-02 1.IOE-03 7.96E-04 AP 07 527529006 11/6/2020 BETA 2.45E-02 1.02E-03 7.59E-04 AP 07 528278006 11/18/2020 BETA 4.46E-02 l.58E-03 1.03E-03 AP 07 529289006 12/2/2020 BETA 2.54E-02 1.15E-03 9.23E-04 AP 07 530489006 12/16/2020 BETA 2.36E-02 1.1 IE-03 9.04E-04 AP 07 531226006 12/30/2020 BETA 2.34E-02 1.12E-03 9.57E-04 AP 07 533257006 12/30/2020 Ac-228 1.IOE-03 6.45E-04 l.54E-03 u AP 07 533257006 12/30/2020 Ag-108m 3.68E-05 5.91E-05 2.04E-04 u AP 07 533257006 12/30/2020 Ag-1 lOm -4.50E-05 1.16E-04 3.49E-04 u AP 07 533257006 12/30/2020 Ba-140 -6.52E-03 1.54E-02 4.88E-02 u AP 07 533257006 12/30/2020 Be-7 8.95E-02 6.80E-03 5.03E-03 AP 07 533257006 12/30/2020 Ce-141 -5.07E-04 3.77E-04 1.05E-03 u AP 07 533257006 12/30/2020 Ce-144 3.41E-04 3.59E-04 1.19E-03 u AP 07 533257006 12/30/2020 Co-57 9.19E-05 4.60E-05 l.49E-04 u AP 07 533257006 12/30/2020 Co-58 -2.27E-05 1.34E-04 4.20E-04 u AP 07 533257006 12/30/2020 Co-60 9.IOE-05 8.71E-05 3.21E-04 u AP 07 533257006 12/30/2020 Cr-51 6.60E-04 3.19E-03 1.IOE-02 u AP 07 533257006 12/30/2020 Cs-134 -2.12E-06 9.09E-05 2.91E-04 u AP 07 533257006 12/30/2020 Cs-137 8.16E-05 8.lOE-05 2.80E-04 u AP 07 533257006 12/30/2020 Fe-59 9.78E-05 4.05E-04 1.41E-03 u AP 07 533257006 12/30/2020 1-131 -3.83E-02 4.96E-02 1.37E-01 u AP 07 533257006 12/30/2020 K-40 5.15E-04 1.41E-03 3.48E-03 u AP 07 533257006 12/30/2020 La-140 -4.39E-03 6.04E-03 1.67E-02 u AP 07 533257006 12/30/2020 Mn-54 8.84E-06 1.02E-04 3.22E-04 u AP 07 533257006 12/30/2020 Nb-95 2.37E-04 1.72E-04 6.00E-04 u AP 07 533257006 12/30/2020 Ru-103 -4.47E-05 2.39E-04 7.81E-04 u AP 07 533257006 12/30/2020 Ru-106 8.74E-04 7.84E-04 2.72E-03 u AP 07 533257006 12/30/2020 Sb-124 -1.41E-04 3.59E-04 1.06E-03 u AP 07 533257006 12/30/2020 Sb-125 -2.43E-05 2.03E-04 6.76E-04 u AP 07 533257006 12/30/2020 Se-75 1.77E-05 1.IOE-04 3.83E-04 u AP 07 533257006 12/30/2020 Th-228 4.28E-05 2.30E-04 3.78E-04 u AP 07 533257006 12/30/2020 Zn-65 1.66E-06 2.32E-04 7.83E-04 u AP 07 533257006 12/30/2020 Zr-95 -6.53E-06 2.90E-04 9.34E-04 u AP 08 501552007 1/15/2020 BETA 2.21E-02 9.84E-04 7.89E-04 AP 08 502825007 1/29/2020 BETA 2.21E-02 l.04E-03 9.13E-04 AP 08 504483007 2/12/2020 BETA 2.29E-02 1.08E-03 9.33E-04 171

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/m3) (pCi/m3) (pCi/m3)

AP 08 505599007 2/26/2020 BETA 3.48E-02 l.26E-03 8.37E-04 AP 08 506904007 3/11/2020 BETA 2.35E-02 l.09E-03 9.27E-04 AP 08 508060006 3/25/2020 BETA 2.30E-02 l.04E-03 8.80E-04 AP 08 510636006 3/25/2020 Ac-228 -3.83E-04 4.61E-04 l.48E-03 u AP 08 510636006 3/25/2020 Ag-108m -1.67E-06 6.86E-05 2.19E-04 u AP 08 510636006 3/25/2020 Ag-llOm 6.40E-05 l.27E-04 4.49E-04 u AP 08 510636006 3/25/2020 Ba-140 9.22E-02 5.18E-02 1.23E-01 u AP 08 510636006 3/25/2020 Be-7 1.l 7E-01 9.73E-03 8.27E-03 AP 08 510636006 3/25/2020 Ce-141 l.06E-04 8.47E-04 l.84E-03 u AP 08 510636006 3/25/2020 Ce-144 -9.81E-05 5.0IE-04 l.64E-03 u AP 08 510636006 3/25/2020 Co-57 -3.26E-05 6.85E-05 2.21E-04 u AP 08 510636006 3/25/2020 Co-58 l.66E-04 l.82E-04 6.38E-04 u AP 08 510636006 3/25/2020 Co-60 -5.90E-05 l.02E-04 3.02E-04 u AP 08 510636006 3/25/2020 Cr-51 -2.46E-03 5.56E-03 l.74E-02 u AP 08 510636006 3/25/2020 Cs-134 -7.87E-05 1.30E-04 3.94E-04 u AP 08 510636006 3/25/2020 Cs-137 2.67E-05 9.31E-05 3.22E-04 u AP 08 510636006 3/25/2020 Fe-59 -l.96E-04 7.0IE-04 2.25E-03 u AP 08 510636006 3/25/2020 I-131 -4.62E-02 1.18E-01 O.OOE+OO u AP 08 510636006 3/25/2020 K-40 2.68E-03 2.60E-03 3.57E-03 u AP 08 510636006 3/25/2020 La-140 -7.19E-03 l.41E-02 4.23E-02 u AP 08 510636006 3/25/2020 Mn-54 7.70E-05 l.06E-04 3.74E-04 u AP 08 510636006 3/25/2020 Nb-95 3.87E-04 2.07E-04 7.46E-04 u AP 08 510636006 3/25/2020 Ru-103 -4.96E-04 3.78E-04 l.OOE-03 u AP 08 510636006 3/25/2020 Ru-106 1.44E-03 l.07E-03 3.76E-03 u AP 08 510636006 3/25/2020 Sb-124 -1.67E-04 4.64E-04 1.37E-03 u AP 08 510636006 3/25/2020 Sb-125 -3.22E-04 2.62E-04 7.25E-04 u AP 08 510636006 3/25/2020 Se-75 2.88E-04 l.74E-04 5.73E-04 u AP 08 510636006 3/25/2020 Th-228 l.35E-04 2.91E-04 5.90E-04 u AP 08 510636006 3/25/2020 Zn-65 -9.76E-05 2.65E-04 8.40E-04 u AP 08 510636006 3/25/2020 Zr-95 3.24E-04 3.74E-04 1.33E-03 u AP 08 509289007 4/9/2020 BETA l.08E-02 7.62E-04 9.79E-04 AP 08 510087007 4/22/2020 BETA 2.61E-02 1.20E-03 9.53E-04 AP 08 510960007 5/6/2020 BETA 2.lOE-02 1.14E-03 1.25E-03 AP 08 511920007 5/20/2020 BETA 2.07E-02 1.03E-03 9.14E-04 AP 08 512893007 6/3/2020 BETA l.78E-02 1.03E-03 1.19E-03 AP 08 514085007 6/17/2020 BETA 2.57E-02 l.25E-03 l.08E-03 AP 08 515124007 7/1/2020 BETA 2.85E-02 1.32E-03 l.08E-03 AP 08 517014007 7/1/2020 Ac-228 6.19E-04 6.99E-04 l.63E-03 u AP 08 517014007 7/1/2020 Ag-108m l.98E-05 6.56E-05 2.24E-04 u AP 08 517014007 7/1/2020 Ag-1 lOm -1.29E-04 1.39E-04 4.05E-04 u AP 08 517014007 7/1/2020 Ba-140 3.48E-02 2.28E-02 8.07E-02 u AP 08 517014007 7/1/2020 Be-7 l.47E-01 l.06E-02 6.57E-03 AP 08 517014007 7/112020 Ce-141 -1.93E-04 5.62E-04 l.68E-03 u AP 08 517014007 7/1/2020 Ce-144 -6.84E-04 4.47E-04 1.23E-03 u AP 08 517014007 711/2020 Co-57 3.62E-05 5.51E-05 l.86E-04 u AP 08 517014007 7/1/2020 Co-58 4.03E-04 2.24E-04 7.46E-04 u AP 08 517014007 7/1/2020 Co-60 -2.71E-05 8.87E-05 2.72E-04 u 172

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/m 3 ) (pCi/m3) (pCi/m3)

AP 08 517014007 7/112020 Cr-51 3.44£-03 4.63£-03 1.62£-02 u AP 08 517014007 7/112020 Cs-134 8.lOE-05 9.32E-05 3.25£-04 u AP 08 517014007 7/112020 Cs-137 4.81E-05 7.68£-05 2.64£-04 u AP 08 517014007 7/l/2020 Fe-59 4.1 IE-05 6.39£-04 2.14£-03 u AP 08 517014007 7/l/2020 I-131 -1.00E-01 8.34£-02 O.OOE+OO u AP 08 517014007 7/1/2020 K-40 2.31£-03 1.69£-03 6.25£-03 u AP 08 517014007 7/112020 La-140 -1.l IE-02 1.IOE-02 2.76£-02 u AP 08 517014007 7/112020 Mn-54 -8.30£-05 1.03£-04 3.14£-04 u AP 08 517014007 7/112020 Nb-95 2.52E-04 1.90£-04 6.73£-04 u AP 08 517014007 7/112020 Ru-103 -6.09£-05 3.14£-04 9.77£-04 u AP 08 517014007 7/112020 Ru-106 2.36£-03 1.06£-03 3.58£-03 u AP 08 517014007 7/112020 Sb-124 7.22£-05 3.98£-04 1.40£-03 u AP 08 517014007 7/112020 Sb-125 8.34£-06 2.38£-04 7.98£-04 u AP 08 517014007 7/112020 Se-75 2.99£-05 1.53£-04 4.82£-04 u AP 08 517014007 7/l/2020 Th-228 3.44E-04 2.60£-04 6.0IE-04 u AP 08 517014007 7/l/2020 Zn-65 6.88£-05 3.06£-04 1.04£-03 u AP 08 517014007 7/l/2020 Zr-95 -2.54£-04 3.13£-04 8.57£-04 u AP 08 5163 58007 7/17/2020 BETA 1.67E-02 9.94£-04 1.06£-03 AP 08 517178007 7/29/2020 BETA 4.14E-02 1.79E-03 1.65£-03 AP 08 518829007 8/12/2020 BETA 4.69£-02 4.29£-03 6.26£-03 AP 08 519921007 8/26/2020 BETA 2.93£-02 1.23£-03 9.55£-04 AP 08 521451007 9/9/2020 BETA 2.37£-02 1.08£-03 8.58£-04 AP 08 522475007 9/23/2020 BETA 2.17£-02 1.06£-03 9.23£-04 AP 08 526420007 9/23/2020 Ac-228 7.31E-04 7.86£-04 2.82£-03 u AP 08 526420007 9/23/2020 Ag-108m -8.22£-05 1.0IE-04 3.1 IE-04 u AP 08 526420007 9/23/2020 Ag-llOm 1.59£-04 2.53£-04 8.77£-04 u AP 08 526420007 9/23/2020 Ba-140 -3.20£-02 5.85£-02 1.83£-01 u AP 08 526420007 9/23/2020 Be-7 1.33£-01 1.18£-02 7.67£-03 AP 08 526420007 9/23/2020 Ce-141 4.77£-04 8.93£-04 3.02£-03 u AP 08 526420007 9/23/2020 Ce-144 6.31E-05 6.47E-04 2.0IE-03 u AP 08 526420007 9/23/2020 Co-57 9.57E-05 8.63£-05 2.95£-04 u AP 08 526420007 9/23/2020 Co-58 -1.07£-04 3.41E-04 1.06£-03 u AP 08 526420007 912312020 Co-60 -3.28£-06 2.19£-04 7.30£-04 u AP 08 526420007 9/23/2020 Cr-51 5.06£-03 1.07E-02 3.40£-02 u AP 08 526420007 9/23/2020 Cs-134 -1.57£-04 1.63£-04 4.21E-04 u AP 08 526420007 9/23/2020 Cs-137 -6.42£-05 1.60£-04 5.04£-04 u AP 08 526420007 9/23/2020 Fe-59 -2.26£-04 9.77£-04 3.19£-03 u AP 08 526420007 9/23/2020 I-131 -2.97£-01 2.86£-01 O.OOE+OO u AP 08 526420007 9/23/2020 K-40 O.OOE+OO 2.67E-03 3.54E-03 u AP 08 526420007 9/23/2020 La-140 9.83£-03 3.lOE-02 1.07E-01 u AP 08 526420007 9/23/2020 Mn-54 1.25£-04 2.00E-04 6.87E-04 u AP 08 526420007 9/23/2020 Nb-95 2.79£-04 3.75E-04 l.31E-03 u AP 08 526420007 9/23/2020 Ru-103 5.41E-05 6.47£-04 2.19£-03 u AP 08 526420007 9/23/2020 Ru-106 3.13£-04 1.58£-03 4.82£-03 u AP 08 526420007 9/23/2020 Sb-124 4.1 IE-04 1.00E-03 3.55£-03 u AP 08 526420007 9/23/2020 Sb-125 -3.55£-04 3.25£-04 9.62£-04 u AP 08 526420007 9/23/2020 Se-75 -6.68£-05 2.40£-04 7.48£-04 u AP 08 526420007 9/23/2020 Th-228 3.0IE-04 3.53£-04 6.67£-04 u AP 08 526420007 9/23/2020 Zn-65 -5.87£-04 5.12E-04 1.43£-03 u 173

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/m3) (pCi/m3) (pCi/m3)

AP 08 526420007 9/23/2020 Zr-95 l.63E-03 7.13E-04 2.59E-03 U AP 08 523935007 1017/2020 BETA 3.62E-02 1.36E-03 9.43E-04 AP 08 525295007 10/21/2020 BETA 2.90E-02 l.21E-03 9.55E-04 AP 08 527529007 11/6/2020 BETA 2.31E-02 l.OIE-03 7.83E-04 AP 08 528278007 11/18/2020 BETA 4.94E-02 l.73E-03 l.21E-03 AP 08 529289007 12/2/2020 BETA 2.87E-02 1.22E-03 9.51E-04 AP 08 530489007 12/16/2020 BETA 2.78E-02 l.18E-03 8.96E-04 AP 08 531226007 12/30/2020 BETA 2.70E-02 l.21E-03 9.79E-04 AP 08 533257007 12/30/2020 Ac-228 9.79E-04 4.61E-04 l.57E-03 u AP 08 533257007 12/30/2020 Ag-108m -7.28E-05 7.25E-05 2.08E-04 u AP 08 533257007 12/30/2020 Ag-llOm 3.81E-04 2.IOE-04 6.llE-04 u AP 08 533257007 12/30/2020 Ba-140 2.75E-02 l.84E-02 6.27E-02 u AP 08 533257007 12/30/2020 Be-7 l.OOE-01 8.07E-03 5.71E-03 AP 08 533257007 12/30/2020 Ce-141 O.OOE+OO 1.52E-03 1.42E-03 u AP 08 533257007 12/30/2020 Ce-144 -1.48E-04 4.59E-04 1.36E-03 u AP 08 533257007 12/30/2020 Co-57 l.99E-05 5.90E-05 l.98E-04 u AP 08 533257007 12/30/2020 Co-58 -1.46E-04 l.49E-04 4.30E-04 u AP 08 533257007 12/30/2020 Co-60 -1.33E-04 l.OIE-04 2.49E-04 u AP 08 533257007 12/30/2020 Cr-51 -3. IOE-03 4.57E-03 1.35E-02 u AP 08 533257007 12/30/2020 Cs-134 -l.56E-04 l.06E-04 2.85E-04 u AP 08 533257007 12/30/2020 Cs-137 2.99E-06 8.90E-05 3.02E-04 u AP 08 533257007 12/30/2020 Fe-59 7.58E-04 5.87E-04 2.12E-03 u AP 08 533257007 12/30/2020 1-131 8.03E-02 6.77E-02 2.25E-01 u AP 08 533257007 12/30/2020 K-40 O.OOE+OO 2.26E-03 3.28E-03 u AP 08 533257007 12/30/2020 La-140 -l.58E-02 9.31E-03 l.86E-02 u AP 08 533257007 12/30/2020 Mn-54 7.53E-06 9.23E-05 3.12E-04 u AP 08 533257007 12/30/2020 Nb-95 -l.96E-04 2.24E-04 5.97E-04 u AP 08 533257007 12/30/2020 Ru-103 -1.12E-04 2.54E-04 7.71E-04 u AP 08 533257007 12/30/2020 Ru-106 -2.17E-04 7.39E-04 2.44E-03 u AP 08 533257007 12/30/2020 Sb-124 -9.21E-04 6.39E-04 1.47E-03 u AP 08 533257007 12/30/2020 Sb-125 -5.76E-05 2.30E-04 7.22E-04 u AP 08 533257007 12/30/2020 Se-75 -1.51E-04 1.54E-04 4.37E-04 u AP 08 533257007 12/30/2020 Th-228 2.88E-04 l.77E-04 5.65E-04 u AP 08 533257007 12/30/2020 Zn-65 -4.07E-04 2.64E-04 6.57E-04 u AP 08 533257007 12/30/2020 Zr-95 -1.86E-04 3.00E-04 9.40E-04 u AP 09 501552008 1115/2020 BETA 2.29E-02 l.02E-03 8.47E-04 AP 09 502825008 1/29/2020 BETA 2.73E-02 l.23E-03 l.OIE-03 AP 09 504483008 2/12/2020 BETA 2.37E-02 l.07E-03 9.15E-04 AP 09 505599008 2/26/2020 BETA 3.72E-02 1.34E-03 8.77E-04 AP 09 506904008 3/11/2020 BETA 2.96E-02 l.35E-03 l.07E-03 AP 09 508060007 3/25/2020 BETA 2.35E-02 1.12E-03 9.58E-04 AP 09 510636007 3/25/2020 Ac-228 l.83E-04 4.17E-04 l.30E-03 u AP 09 510636007 3/25/2020 Ag-108m -2.33E-05 6.80E-05 2.25E-04 u AP 09 510636007 3/25/2020 Ag-11 Om -2.56E-04 l.45E-04 3.02E-04 u AP 09 510636007 3/25/2020 Ba-140 -l.64E-02 2.30E-02 7.04E-02 u AP 09 510636007 3/25/2020 Be-7 1.18E-01 8.63E-03 5.69E-03 174

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/m3 ) (pCi/m3 ) (pCi/m3)

AP 09 510636007 3/25/2020 Ce-141 -4.17E-04 5.lOE-04 l.56E-03 u AP 09 510636007 3/25/2020 Ce-144 8.00E-04 4.08E-04 l.33E-03 u AP 09 510636007 3/25/2020 Co-57 l.18E-05 4.94E-05 1.64E-04 u AP 09 510636007 3/25/2020 Co-58 -l.69E-04 l.75E-04 4.87E-04 u AP 09 510636007 3/25/2020 Co-60 l.48E-04 l.18E-04 4.53E-04 u AP 09 510636007 3/25/2020 Cr-51 2.94E-03 4.83E-03 l.55E-02 u AP 09 510636007 3/25/2020 Cs-134 -l.32E-05 8.98E-05 2.87E-04 u AP 09 510636007 3/25/2020 Cs-137 l.66E-04 9.57E-05 3.15E-04 u AP 09 510636007 3/25/2020 Fe-59 -4.36E-04 6.6IE-04 l.88E-03 u AP 09 510636007 3/25/2020 1-131 O.OOE+OO l.07E-Ol O.OOE+OO UI AP 09 510636007 3/25/2020 K-40 O.OOE+OO l.89E-03 2.49E-03 u AP 09 510636007 3/25/2020 La-140 3.19E-03 l.02E-02 3.53E-02 u AP 09 510636007 3/25/2020 Mn-54 -5.37E-05 9.25E-05 2.76E-04 u AP 09 510636007 3/25/2020 Nb-95 -l.71E-04 2.15E-04 6.36E-04 u AP 09 510636007 3/25/2020 Ru-103 l.09E-04 2.68E-04 9.27E-04 u AP 09 510636007 3/25/2020 Ru-106 -8.13E-05 6.77E-04 2.21E-03 u AP 09 510636007 3/25/2020 Sb-124 3.67E-04 4.58E-04 l.71E-03 u AP 09 510636007 3/25/2020 Sb-125 -2.20E-04 l.80E-04 5.24E-04 u AP 09 510636007 3/25/2020 Se-75 5.15E-05 l.30E-04 4.19E-04 u AP 09 510636007 3/25/2020 Th-228 7.52E-04 2.97E-04 3.58E-04 AP 09 510636007 3/25/2020 Zn-65 l.98E-04 2.31E-04 8.02E-04 u AP 09 510636007 3/25/2020 Zr-95 -l.58E-05 3.27E-04 l.06E-03 u AP 09 509289008 4/9/2020 BETA l.76E-02 9.50E-04 8.96E-04 AP 09 510087008 4/22/2020 BETA 2.14E-02 l.17E-03 1.12E-03 AP 09 510960008 5/6/2020 BETA l.94E-02 9.99E-04 9.24E-04 AP 09 511920008 5/20/2020 BETA l.74E-02 9.97E-04 9.67E-04 AP 09 512893008 6/3/2020 BETA l.79E-02 l.04E-03 l.08E-03 AP 09 514085008 6/17/2020 BETA 2.16E-02 l.14E-03 l.07E-03 AP 09 515124008 7/l/2020 BETA 2.41E-02 l.19E-03 l.05E-03 AP 09 517014008 7/112020 Ac-228 O.OOE+OO 6.63E-04 l.58E-03 u AP 09 517014008 7/112020 Ag-108m 4.69E-05 7.12E-05 2.33E-04 u AP 09 517014008 7/l/2020 Ag-1 IOm 7.48E-05 l.58E-04 4.66E-04 u AP 09 517014008 7/l/2020 Ba-140 -l.48E-02 2.03E-02 6.45E-02 u AP 09 517014008 7/112020 Be-7 l.53E-Ol l.OIE-02 5.53E-03 AP 09 517014008 7/112020 Ce-141 l.18E-03 6.05E-04 1.76E-03 u AP 09 517014008 7/112020 Ce-144 6.48E-04 5.17E-04 l.65E-03 u AP 09 517014008 7/l/2020 Co-57 4.73E-05 6.52E-05 2.lOE-04 u AP 09 517014008 7/112020 Co-58 -2.13E-04 l.64E-04 4.45E-04 u AP 09 517014008 7/112020 Co-60 -l.52E-04 9.52E-05 2.31E-04 u AP 09 517014008 7/112020 Cr-51 l.50E-03 4.56E-03 l.51E-02 u AP 09 517014008 7/112020 Cs-134 l.17E-05 9.75E-05 3.21E-04 u AP 09 517014008 7/1/2020 Cs-137 5.61E-05 8.48E-05 2.90E-04 u AP 09 517014008 71112020 Fe-59 -4.02E-05 6.63E-04 l.92E-03 u AP 09 517014008 7/1/2020 1-131 O.OOE+OO 8.26E-02 O.OOE+OO UI AP 09 517014008 71112020 K-40 l.46E-03 2.08E-03 2.48E-03 u AP 09 517014008 7/112020 La-140 -5.52E-03 9.73E-03 2.93E-02 u AP 09 517014008 71112020 Mn-54 -1.69E-04 1.27E-04 3.59E-04 u AP 09 517014008 7/112020 Nb-95 -2.91E-04 l.93E-04 5.15E-04 u AP 09 517014008 7/l/2020 Ru-103 -3.90E-04 2.90E-04 8.60E-04 u 175

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/m3) (pCi/m3) (pCi/m3)

AP 09 517014008 7/112020 Ru-106 -1.67E-04 8.19E-04 2.70E-03 u AP 09 517014008 7/112020 Sb-124 2.56E-04 5.33E-04 l.80E-03 u AP 09 517014008 7/112020 Sb-125 1.56E-04 2.20E-04 7.25E-04 u AP 09 517014008 711/2020 Se-75 -5.83E-05 1.47E-04 4.78E-04 u AP 09 517014008 7/l/2020 Th-228 -5.38E-05 1.64E-04 5.66E-04 u AP 09 517014008 7/l/2020 Zn-65 -1.61E-04 2.55E-04 8.06E-04 u AP 09 517014008 7/112020 Zr-95 1.42E-06 3.67E-04 1.21E-03 u AP 09 516358008 7/14/2020 BETA 2.05E-02 1.21E-03 1.21E-03 AP 09 517178008 7/29/2020 BETA 3.38E-02 1.51E-03 l.23E-03 AP 09 518829008 8/12/2020 BETA 3.30E-02 1.25E-03 8.99E-04 AP 09 519921008 8/26/2020 BETA 2.67E-02 1.13E-03 8.72E-04 AP 09 521451008 9/9/2020 BETA 2.21E-02 1.04E-03 9.68E-04 AP 09 522475008 9/23/2020 BETA 1.69E-02 8.89E-04 8.46E-04 AP 09 526420008 9/23/2020 Ac-228 -5.60E-04 4.51E-04 1.36E-03 u AP 09 526420008 9/23/2020 Ag-108m -7.84E-05 5.82E-05 1.67E-04 u AP 09 526420008 9/23/2020 Ag-llOm -6.45E-05 1.54E-04 4.47E-04 u AP 09 526420008 9/23/2020 Ba-140 -3.69E-03 3.0IE-02 1.00E-01 u AP 09 526420008 9/23/2020 Be-7 1.30E-01 9.21E-03 5.1 IE-03 AP 09 526420008 9/23/2020 Ce-141 -5.70E-04 6.61E-04 1.76E-03 u AP 09 526420008 9/23/2020 Ce-144 -3.85E-04 3.93E-04 1.19E-03 u AP 09 526420008 9/23/2020 Co-57 7.00E-05 5.35E-05 1.82E-04 u AP 09 526420008 9/23/2020 Co-58 8.64E-05 1.70E-04 5.39E-04 u AP 09 526420008 9/23/2020 Co-60 6.67E-05 1.17E-04 4.17E-04 u AP 09 526420008 9/23/2020 Cr-51 -6.57E-03 5.91E-03 1.46E-02 u AP 09 526420008 9/23/2020 Cs-134 1.63E-04 1.22E-04 3.32E-04 u AP 09 526420008 9/23/2020 Cs-137 -3.23E-05 8.35E-05 2.66E-04 u AP 09 526420008 9/23/2020 Fe-59 1.00E-03 7.48E-04 2.66E-03 u AP 09 526420008 9/23/2020 I-131 O.OOE+OO 1.57E-01 O.OOE+OO UI AP 09 526420008 9/23/2020 K-40 9.02E-04 1.38E-03 5.05E-03 u AP 09 526420008 9/23/2020 La-140 -1.36E-02 1.27E-02 3.13E-02 u AP 09 526420008 9/23/2020 Mn-54 1.96E-04 7.61E-05 2.69E-04 u AP 09 526420008 9/23/2020 Nb-95 3.31E-04 2.18E-04 7.72E-04 u AP 09 526420008 9/23/2020 Ru-103 2.79E-04 2.92E-04 1.04E-03 u AP 09 526420008 9/23/2020 Ru-106 -8.78E-04 9.00E-04 2.65E-03 u AP 09 526420008 9/23/2020 Sb-124 2.83E-04 6.80E-04 2.38E-03 u AP 09 526420008 9/23/2020 Sb-125 -1.20E-05 1.84E-04 6.25E-04 u AP 09 526420008 9/23/2020 Se-75 1.IOE-04 1.43E-04 4.72E-04 u AP 09 526420008 9/23/2020 Th-228 3.51E-04 1.81E-04 5.16E-04 u AP 09 526420008 9/23/2020 Zn-65 2.55E-04 2.31E-04 8.25E-04 u AP 09 526420008 9/23/2020 Zr-95 1.55E-04 3.85E-04 1.31E-03 u AP 09 523935008 1017/2020 BETA 3.17E-02 1.17E-03 7.74E-04 AP 09 525295008 10/2112020 BETA 2.12E-02 9.77E-04 7.85E-04 176

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/m 3 ) (pCi/m 3 ) (pCi/m 3 )

AP 09 527529008 11/6/2020 BETA 2.02E-02 8.57E-04 6.27E-04 AP 09 528278008 11118/2020 BETA 4.86E-02 I .59E-03 9.76E-04 AP 09 529289008 12/2/2020 BETA l .27E-02 7.44E-04 7.47E-04 AP 09 530489008 12/16/2020 BETA 2.51E-02 l.04E-03 7.76E-04 AP 09 531226008 12/30/2020 BETA 2.46E-02 9.89E-04 7.54E-04 AP 09 533257008 12/30/2020 Ac-228 3.49E-04 3.33E-04 5.64E-04 u AP 09 533257008 12/30/2020 Ag-108m O.OOE+OO 7.58E-05 l.57E-04 u AP 09 533257008 12/30/2020 Ag-1 lOm 1.71 E-04 l. l lE-04 4.0lE-04 u AP 09 533257008 12/30/2020 Ba-140 l.54E-02 l.32E-02 4.27E-02 u AP 09 533257008 12/30/2020 Be-7 8.60E-02 6.25E-03 4.59E-03 AP 09 533257008 12/30/2020 Ce-141 l.47E-04 7.20E-04 1.16E-03 u AP 09 533257008 12/30/2020 Ce-144 l.76E-04 3.02E-04 l.OOE-03 u AP 09 533257008 12/30/2020 Co-57 -1.18E-05 4.41E-05 l.31E-04 u AP 09 533257008 12/30/2020 Co-58 l.21E-05 I .19E-04 3.81E-04 u AP 09 533257008 12/30/2020 Co-60 3.54E-05 8.07E-05 2.77E-04 u AP 09 533257008 12/30/2020 Cr-51 6.04E-04 2.94E-03 1.01 E-02 u AP 09 533257008 12/30/2020 Cs-134 -6.87E-05 8.13E-05 2.21E-04 u AP 09 533257008 12/30/2020 Cs-137 2.76E-05 5.81E-05 l.95E-04 u AP 09 533257008 12/30/2020 Fe-59 6.32E-05 3.31 E-04 1.09E-03 u AP 09 533257008 12/30/2020 1-131 l.20E-02 4.13E-02 1.41E-Ol u AP 09 533257008 12/30/2020 K-40 3.59E-04 9.83E-04 I .63E-03 u AP 09 533257008 12/30/2020 La-140 4.92E-04 5.47E-03 I .68E-02 u AP 09 533257008 12/30/2020 Mn-54 -l.89E-06 5.09E-05 l.72E-04 u AP 09 533257008 12/30/2020 Nb-95 2.90E-05 l.34E-04 4.35E-04 u AP 09 533257008 12/30/2020 Ru-103 -2.47E-04 2.08E-04 5.93E-04 u AP 09 533257008 12/30/2020 Ru-106 -2.60E-04 5.48E-04 I .68E-03 u AP 09 533257008 12/30/2020 Sb-124 5.50E-04 4.56E-04 l.69E-03 u AP 09 533257008 12/30/2020 Sb-125 l.74E-04 l.75E-04 6.03E-04 u AP 09 533257008 12/30/2020 Se-75 -l.22E-04 l.07E-04 3.33E-04 u AP 09 533257008 12/30/2020 Th-228 2.92E-04 l.85E-04 4.36E-04 u AP 09 533257008 12/30/2020 Zn-65 -3.19E-04 l .61E-04 3.00E-04 u AP 09 533257008 12/30/2020 Zr-95 -l.08E-04 2.27E-04 6.78E-04 U 177

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/m3 ) (pCi/m3) (pCi/m3)

CF 01 501552009 1/15/2020 1-131 2.54E-03 2.28E-03 7.91E-03 u CF 01 502825009 1/29/2020 1-131 3.84E-03 l.93E-03 5.l lE-03 u CF 01 504483009 2/12/2020 1-131 -9.72E-05 2.36E-03 7.94E-03 u CF 01 505599009 2/26/2020 1-131 -1.15E-03 l.95E-03 6.21E-03 u CF 01 506904009 311112020 I-131 -6.30E-04 l.35E-03 4.29E-03 u CF 01 508060008 3/25/2020 I-131 l.96E-03 l.72E-03 5.94E-03 u CF 01 509289009 4/9/2020 I-131 3.65E-04 l.80E-03 6.02E-03 u CF 01 510087009 4/22/2020 I-131 l.53E-03 l.74E-03 6.llE-03 u CF 01 510960009 51612020 I-131 2.40E-04 l.60E-03 5.25E-03 u CF 01 511920009 5/20/2020 I-131 O.OOE+OO 2.32E-03 4.28E-03 u CF 01 512893009 6/3/2020 I-131 l.05E-03 l.37E-03 4.88E-03 u CF 01 514085009 6/17/2020 I-131 -2.48E-03 3.02E-03 9.25E-03 u CF 01 515124009 7/1/2020 I-131 -1.52E-03 4.20E-03 l.39E-02 u CF 01 516358009 7/17/2020 I-131 -7.26E-03 4.17E-03 l.04E-02 u CF 01 517178009 7/29/2020 I-131 -2.02E-04 l.16E-02 3.83E-02 u CF 01 518829009 8/12/2020 I-131 2.03E-02 l.63E-02 5.88E-02 u CF 01 519921009 8/26/2020 I-131 -6.42E-04 l.95E-03 6.26E-03 u CF 01 521451009 9/9/2020 I-131 l.98E-03 3.72E-03 l.31E-02 u CF 01 522475009 9/23/2020 I-131 l.89E-03 l.43E-03 4.90E-03 u CF 01 523935009 101712020 I-131 -9.23E-04 l.59E-03 5.0lE-03 u CF 01 525295009 1012112020 I-131 -1.50E-03 l.56E-03 4.54E-03 u CF 01 527529009 111612020 I-131 3.46E-03 3.32E-03 l.18E-02 u CF 01 528278009 11118/2020 1-131 -2.21E-03 2.14E-03 6.04E-03 u CF 01 529289009 12/2/2020 I-131 -1.12E-03 2.14E-03 6.82E-03 u CF 01 530489009 12/16/2020 I-131 3.81E-04 l.29E-03 4.40E-03 u CF 01 531226009 12/30/2020 I-131 -2.32E-03 2.30E-03 6.00E-03 u CF 02 501552010 111512020 I-131 -8.llE-04 l.50E-03 4.71E-03 u CF 02 502825010 112912020 I-131 -3.68E-03 l.65E-03 3.17E-03 u CF 02 504483010 2/12/2020 I-131 -1.13E-03 2.35E-03 6.60E-03 u CF 02 505599010 212612020 I-131 -1.12E-03 2.54E-03 8.15E-03 u CF 02 506904010 311112020 I-131 l.73E-03 2.58E-03 8.80E-03 u CF 02 508060009 3/25/2020 I-131 l.06E-03 2.69E-03 9.0lE-03 u CF 02 509289010 4/9/2020 I-131 -6.85E-04 l.30E-03 3.87E-03 u CF 02 510087010 4/22/2020 I-131 -l.99E-03 l.38E-03 3.76E-03 u CF 02 510960010 51612020 I-131 l.05E-03 l.29E-03 4.58E-03 u CF 02 511920010 512012020 I-131 -2.70E-03 2.38E-03 6.92E-03 u CF 02 512893010 6/3/2020 I-131 -3.41E-04 l.54E-03 5.07E-03 u CF 02 514085010 6/17/2020 I-131 l.08E-03 l.32E-03 4.71E-03 u CF 02 515124010 7/1/2020 I-131 l.03E-02 4.43E-03 l.26E-02 u CF 02 516358010 7/17/2020 I-131 -2.55E-04 2.67E-03 8.60E-03 u CF 02 517178010 7/29/2020 I-131 -l.OOE-03 3.75E-03 l.llE-02 u CF 02 518829010 8/12/2020 I-131 7.96E-04 l.79E-03 6.00E-03 u CF 02 519921010 8/26/2020 I-131 1.28E-03 l.67E-03 5.74E-03 u CF 02 521451010 91912020 I-131 9.21E-03 4.76E-03 l.68E-02 u CF 02 522475010 9/23/2020 I-131 -l.04E-03 l.56E-03 4.92E-03 u CF 02 523935010 101712020 I-131 O.OOE+OO 2.95E-03 5.25E-03 u CF 02 525295010 1012112020 I-131 l.53E-03 2.16E-03 7.47E-03 u CF 02 527529010 111612020 I-131 -2.0lE-03 4.28E-03 l.36E-02 u CF 02 528278010 11118/2020 I-131 2.32E-03 2.45E-03 8.81E-03 u CF 02 529289010 12/2/2020 I-131 -7.58E-04 2.89E-03 8.28E-03 u 178

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/m3) (pCi/m3) (pCi/m3)

CF 02 530489010 12/16/2020 1-131 -1.08E-03 1.73E-03 5.38E-03 u CF 02 531226010 12/30/2020 1-131 -1.86E-03 2.1 IE-03 6.17E-03 u CF 03 501552011 1/15/2020 1-131 3.82E-03 1.67E-03 6.39E-03 u CF 03 502825011 1/29/2020 1-131 -2.24E-03 1.77E-03 4.97E-03 u CF 03 504483011 2/12/2020 1-131 2.26E-03 2.42E-03 8.62E-03 u CF 03 505599011 2/26/2020 1-131 2.61E-05 3.60E-03 1.18E-02 u CF 03 506904011 3/11/2020 1-131 2.33E-03 1.75E-03 6.18E-03 u CF 03 508060010 3/25/2020 1-131 -1.86E-03 2.19E-03 6.32E-03 u CF 03 509289011 4/9/2020 1-131 -1.93E-03 1.87E-03 5.52E-03 u CF 03 510087011 4/22/2020 1-131 1.38E-03 2.21E-03 7.54E-03 u CF 03 510960011 5/6/2020 1-131 1.47E-04 1.46E-03 4.84E-03 u CF 03 511920011 5/20/2020 1-131 -1.05E-03 2.48E-03 8.19E-03 u CF 03 512893011 6/3/2020 1-131 4.90E-04 1.41E-03 4.75E-03 u CF 03 514085011 6/17/2020 1-131 1.19E-03 2.00E-03 6.94E-03 u CF 03 515124011 7/1/2020 1-131 -5.72E-04 2.45E-03 8.05E-03 u CF 03 516358011 7/17/2020 1-131 5.23E-04 2.47E-03 8.53E-03 u CF 03 517178011 7/29/2020 1-131 7.53E-03 4.23E-03 7.89E-03 u CF 03 518829011 8/12/2020 1-131 -9.61E-05 2.50E-03 8.46E-03 u CF 03 519921011 8/26/2020 1-131 -4.40E-04 1.57E-03 5.15E-03 u CF 03 521451011 9/9/2020 1-131 -5.02E-04 4.93E-03 1.16E-02 u CF 03 522475011 9/23/2020 1-131 O.OOE+OO 2.37E-03 5.72E-03 u CF 03 523935011 1017/2020 1-131 2.39E-05 l.69E-03 5.37E-03 u CF 03 525295011 10/21/2020 1-131 -1.69E-03 1.81E-03 5.48E-03 u CF 03 527529011 11/6/2020 1-131 3.26E-03 4.16E-03 l.47E-02 u CF 03 528278011 11/18/2020 1-131 4.59E-03 2.68E-03 9.48E-03 u CF 03 529289011 12/2/2020 1-131 -1.59E-03 2.83E-03 9.15E-03 u CF 03 530489011 12/16/2020 1-131 -8.88E-04 1.66E-03 5.36E-03 u CF 03 531226011 12/30/2020 1-131 -3.58E-03 2.43E-03 6.27E-03 u CF 04 501552012 1/15/2020 1-131 -3.57E-05 1.47E-03 4.89E-03 u CF 04 502825012 1/29/2020 1-131 -3.IOE-03 2.IOE-03 5.65E-03 u CF 04 504483012 2/12/2020 1-131 1.84E-04 2.lOE-03 6.59E-03 u CF 04 505599012 2/26/2020 1-131 -2.70E-03 2.92E-03 8.61E-03 u CF 04 506904012 3/11/2020 1-131 -1.23E-03 1.17E-03 3.32E-03 u CF 04 508060011 3/25/2020 1-131 -2.30E-03 2.02E-03 5.82E-03 u CF 04 509289012 4/9/2020 1-131 6.06E-05 1.43E-03 4.85E-03 u CF 04 510087012 4/22/2020 1-131 -7.12E-04 1.37E-03 4.26E-03 u CF 04 510960012 5/6/2020 1-131 O.OOE+OO 9.40E-04 2.71E-03 u CF 04 511920012 5/20/2020 1-131 -3.99E-05 1.80E-03 6.07E-03 u CF 04 512893012 6/3/2020 1-131 -6.42E-04 1.67E-03 5.52E-03 u CF 04 514085012 6/17/2020 1-131 -7.54E-04 1.44E-03 4.00E-03 u CF 04 515124012 7/1/2020 1-131 -2.53E-03 2.52E-03 7.43E-03 u CF 04 516358012 7/17/2020 1-131 -2.54E-03 2.16E-03 6.08E-03 u CF 04 517178012 7/29/2020 1-131 3.79E-03 2.97E-03 1.0IE-02 u CF 04 518829012 8/12/2020 1-131 -2.37E-03 2.15E-03 5.14E-03 u CF 04 519921012 8/26/2020 1-131 -1.75E-03 1.51E-03 4.26E-03 u CF 04 521451012 9/9/2020 1-131 -3.06E-03 4.89E-03 1.56E-02 u CF 04 522475012 9/23/2020 1-131 1.88E-03 1.45E-03 5.09E-03 u CF 04 523935012 1017/2020 1-131 -2.70E-03 l.95E-03 4.12E-03 u CF 04 525295012 10/21/2020 1-131 -I.25E-03 1.94E-03 6.12E-03 u 179

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/m3) (pCi/m3 ) * (pCi/m3 )

CF 04 527529012 11/6/2020 I-131 -8.l lE-04 6.18E-03 2.07E-02 u CF 04 528278012 11/18/2020 I-131 -1.06E-03 2.82E-03 9.31£-03 u CF 04 529289012 12/2/2020 I-131 -3.46E-04 2.03E-03 6.60E-03 u CF 04 530489012 12/16/2020 I-131 -4.21£-04 1.28E-03 4.15E-03 u CF 04 531226012 12/30/2020 I-131 -2.14E-03 2.02E-03 5.79E-03 u CF 05 501552013 1/15/2020 I-131 2.40E-03 1.62E-03 5.87E-03 u CF 05 502825013 1/29/2020 I-131 1.04E-03 1.32E-03 4.48E-03 u CF 05 504483013 2/12/2020 I-131 2.82E-03 2.69E-03 9.34E-03 u CF 05 505599013 2/26/2020 I-131 2.07E-03 3.09E-03 1.06E-02 u CF 05 506904013 3/11/2020 1-131 -1.50E-03 l.84E-03 5.59E-03 u CF 05 508060016 3/30/2020 I-131 1.54E-03 2.18E-03 7.48E-03 u CF 05 509289013 4/9/2020 1-131 2.87E-03 3.64E-03 1.29E-02 u CF 05 510087013 4/22/2020 I-131 -2.21£-04 1.75E-03 5.88E-03 u CF 05 510960013 5/6/2020 I-131 5.36E-04 1.74E-03 6.00E-03 u CF 05 511920013 5/20/2020 I-131 -7.86E-04 2.02E-03 6.42E-03 u CF 05 512893013 6/3/2020 I-131 O.OOE+OO 3.42E-03 4.31E-03 u CF 05 514085013 6/17/2020 I-131 5.04E-04 1.61E-03 5.43E-03 u CF 05 515124013 7/1/2020 I-131 -2.25E-03 2.84E-03 8.77E-03 u CF 05 516358013 7/17/2020 I-131 2.03E-03 2.12E-03 7.59E-03 u CF 05 517178013 7/29/2020 I-131 3.55E-03 3.27E-03 1.13E-02 u CF 05 518829013 8/12/2020 I-131 2.89E-03 3.52E-03 l.27E-02 u CF 05 519921013 8/26/2020 I-131 8.29E-04 1.31£-03 4.62E-03 u CF 05 521451013 9/9/2020 I-131 -1.86E-03 4.lOE-03 1.25E-02 u CF 05 522475013 9/23/2020 I-131 3.16E-05 1.50E-03 4.86E-03 u CF 05 523935013 1017/2020 I-131 -7.91£-04 1.95E-03 6.03E-03 u CF 05 525295013 10/21/2020 I-131 -1.03E-03 1.57E-03 4.99E-03 u CF 05 527529013 11/6/2020 I-131 -2.34E-03 3.85E-03 1.17E-02 u CF 05 528278013 11/18/2020 I-131 4.25E-03 2.46E-03 8.99E-03 u CF 05 529289013 12/2/2020 J-131 3.15E-03 2.39E-03 8.53E-03 u CF 05 530489013 12/16/2020 I-131 -1.62E-03 1.49E-03 4.29E-03 u CF 05 531226013 12/30/2020 I-131 -3.91£-03 2.32E-03 5.84E-03 u CF 07 501552014 1/15/2020 I-131 -1.80E-03 1.17E-03 3. l lE-03 u CF 07 502825014 1129/2020 I-131 1.68E-03 1.30E-03 4.74E-03 u CF 07 504483014 2/12/2020 I-131 7.60E-04 1.37E-03 4.92E-03 u CF 07 505599014 2/26/2020 I-131 -4.19E-04 1.57E-03 5.16E-03 u CF 07 506904014 3/11/2020 I-131 4.08E-04 1.12E-03 3.92E-03 u CF 07 508060012 3/25/2020 I-131 -4.71£-04 1.51E-03 4.80E-03 u CF 07 509289014 4/9/2020 I-131 -3.lOE-03 1.85E-03 4.86E-03 u CF 07 510087014 4/22/2020 I-131 4.39E-04 1.51E-03 5.25E-03 u CF 07 510960014 5/6/2020 I-131 2.73E-03 1.95E-03 6.94E-03 u CF 07 511920014 5/20/2020 I-131 -2.02E-03 1.77E-03 5.02E-03 u CF 07 512893014 6/3/2020 I-131 -4.95E-04 1.59E-03 5. l lE-03 u CF 07 514085014 6/17/2020 I-131 -5.35E-04 l.55E-03 5.08E-03 u CF 07 515124014 7/1/2020 I-131 3.71£-03 2.55E-03 9.14E-03 u CF 07 516358014 7/17/2020 I-131 -1.56E-03 2.39E-03 6.92E-03 u CF 07 517178014 7/29/2020 I-131 -1.61£-03 3.84E-03 1.27E-02 u CF 07 518829014 8/12/2020 I-131 8.79E-04 1.89E-03 6.64E-03 u CF 07 519921014 8/26/2020 1-131 4.56E-04 1.46E-03 4.82E-03 u CF 07 521451014 9/9/2020 1-131 -8.00E-04 2.66E-03 8.77E-03 u CF 07 522475014 9/23/2020 1-131 -3.46E-04 1.69E-03 5.62E-03 u 180

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/m3) (pCi/m3) (pCi/m3)

CF 07 523935014 1017/2020 1-131 O.OOE+OO 1.41E-03 4.53E-03 u CF 07 525295014 10/2112020 1-131 8.72E-04 l.43E-03 5.03E-03 u CF 07 527529014 11/6/2020 1-131 -2.00E-03 3.00E-03 9.17E-03 u CF 07 528278014 11118/2020 1-131 3.72E-03 2.42E-03 8.55E-03 u CF 07 529289014 12/2/2020 1-131 -3.25E-03 2.22E-03 5.37E-03 u CF 07 530489014 12/16/2020 1-131 -l.08E-03 1.29E-03 3.91E-03 u CF 07 531226014 12/30/2020 1-131 -l.20E-03 2.18E-03 7.00E-03 u CF 08 501552015 1115/2020 1-131 O.OOE+OO 1.48E-03 3.45E-03 u CF 08 502825015 1129/2020 1-131 -l.07E-03 1.45E-03 4.47E-03 u CF 08 504483015 2/12/2020 1-131 -4.16E-04 2.00E-03 6.59E-03 u CF 08 505599015 2/26/2020 1-131 3.80E-03 2.87E-03 9.92E-03 u CF 08 506904015 3/11/2020 1-131 -4.80E-04 1.48E-03 4.91E-03 u CF 08 508060013 3/25/2020 1-131 -1.64E-03 2.59E-03 7.75E-03 u CF 08 509289015 4/9/2020 1-131 3.77E-05 l.47E-03 5.0lE-03 u CF 08 510087015 4/22/2020 1-131 l.74E-03 l.70E-03 5.93E-03 u CF 08 510960015 5/6/2020 1-131 3.0lE-04 l.43E-03 4.87E-03 u CF 08 511920015 5/20/2020 1-131 -l.43E-03 2.31E-03 7.43E-03 u CF 08 512893015 6/3/2020 1-131 -2.13E-04 1.43E-03 4.81E-03 u CF 08 514085015 6/17 /2020 1-131 -1.43E-03 2.95E-03 9.43E-03 u CF 08 515124015 7/112020 1-131 3.24E-03 2.94E-03 l.04E-02 u CF 08 516358015 7117/2020 1-131 -2.41E-05 2.02E-03 6.77E-03 u CF 08 517178015 7/29/2020 1-131 2.64E-03 2.82E-03 l.OOE-02 u CF 08 518829015 8/12/2020 1-131 8.63E-04 l.24E-02 4.21E-02 u CF 08 519921015 8/26/2020 1-131 2.37E-04 l.24E-03 4.20E-03 u CF 08 521451015 9/9/2020 1-131 4.68E-04 3.22E-03 l.08E-02 u CF 08 522475015 9/23/2020 1-131 2.81E-03 l.58E-03 5.64E-03 u CF 08 523935015 1017/2020 1-131 l.17E-04 l.48E-03 5.02E-03 u CF 08 525295015 10/2112020 1-131 -3.14E-04 2.14E-03 6.53E-03 u CF 08 527529015 1116/2020 1-131 l.60E-03 3.51E-03 l.23E-02 u CF 08 528278015 11118/2020 1-131 3.12E-05 2.56E-03 8.25E-03 u CF 08 529289015 12/2/2020 1-131 -7.27E-04 l.91E-03 6.25E-03 u CF 08 530489015 12/16/2020 1-131 2.51E-03 1.47E-03 5.28E-03 u CF 08 531226015 12/30/2020 1-131 5.08E-04 2.00E-03 6.95E-03 u CF 09 501552016 1/15/2020 1-131 -1.28E-03 1.57E-03 4.85E-03 u CF 09 502825016 1129/2020 1-131 -2.08E-04 l.36E-03 4.55E-03 u CF 09 504483016 2/12/2020 1-131 O.OOE+OO 3.13E-03 4.99E-03 u CF 09 505599016 2/26/2020 1-131 4.33E-03 2.65E-03 9.54E-03 u CF 09 506904016 3/1112020 1-131 2.18E-05 l.35E-03 4.60E-03 u CF 09 508060014 3/25/2020 1-131 -8.03E-04 2.07E-03 6.74E-03 u CF 09 509289016 4/9/2020 1-131 -4.48E-04 1.92E-03 6.03E-03 u CF 09 510087016 4/22/2020 1-131 -1.07E-03 l.71E-03 5.40E-03 u CF 09 510960016 5/6/2020 1-131 2.29E-03 l.75E-03 6.04E-03 u CF 09 511920016 5/20/2020 1-131 -9.87E-04 l.76E-03 5.62E-03 u CF 09 512893016 6/3/2020 1-131 l.39E-04 l.70E-03 5.81E-03 u CF 09 514085016 6/17/2020 1-131 l.71E-03 l.99E-03 7.05E-03 u CF 09 515124016 7/112020 1-131 4.17E-03 2.51E-03 9.0lE-03 u CF 09 516358016 7/14/2020 1-131 -2.16E-03 4.0lE-03 l.28E-02 u CF 09 517178016 7/29/2020 1-131 -4.64E-03 2.91E-03 7.33E-03 u CF 09 518829016 8/12/2020 1-131 -l.71E-03 1.96E-03 5.74E-03 u 181

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/m3) (pCi/m3) (pCi/m3)

CF 09 519921016 8/26/2020 I-131 -1.34E-03 1.65E-03 4.97E-03 u CF 09 521451016 91912020 I-131 -3.35E-03 3.69E-03 l.14E-02 u CF 09 522475016 912312020 I-131 2.29E-03 2.33E-03 3.48E-03 u CF 09 523935016 101712020 I-131 1.94E-04 1.39E-03 4.54E-03 u CF 09 525295016 10/21/2020 I-131 2.72E-03 1.25E-03 4.46E-03 u CF 09 527529016 11/6/2020 I-131 2.09E-03 5.31E-03 l.84E-02 u CF 09 528278016 11/18/2020 I-131 -3.49E-04 2.19E-03 6.48E-03 u CF 09 529289016 12/2/2020 I-131 -2.33E-04 2.35E-03 7.81E-03 u CF 09 530489016 12/16/2020 I-131 9.63E-04 9.41E-04 3.43E-03 u CF 09 531226016 12/30/2020 I-131 -6.l lE-04 2.72E-03 9.15E-03 u 182

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/kg) (pCi/kg) (pCi/kg)

FH 03 518929001 8/10/2020 Ac-228 -8.38E+OO l.21E+Ol 3.61E+Ol u FH 03 518929001 8/10/2020 Ag-108m -7.67E-03 l.68E+OO 5.56£+00 u FH 03 518929001 8/10/2020 Ag-11 Om -4.54E-Ol 3.45£+00 l.IOE+Ol u FH 03 518929001 8/10/2020 Ba-140 6.36E+OO l.25E+Ol 4.23£+01 u FH 03 518929001 8/10/2020 Be-7 -9.94E+OO 2.05E+Ol 6.48£+01 u FH 03 518929001 8/10/2020 Bi-214 -4.25E-Ol 6.37E+OO 1.64£+01 u FH 03 518929001 8/10/2020 Ce-141 -2.44£+00 4.00E+OO l.31E+Ol u FH 03 518929001 8/10/2020 Ce-144 -l.90E+OO l.29E+Ol 4.36£+01 u FH 03 518929001 8/10/2020 Co-57 -2.19E+OO l.80E+OO 5.57£+00 u FH 03 518929001 8/10/2020 Co-58 -9.21E-Ol 2.82£+00 8.85£+00 u FH 03 518929001 8/10/2020 Co-60 6.38E+OO 3.73£+00 1.28£+01 u FH 03 518929001 8/10/2020 Cr-51 l.21E+Ol 2.13E+Ol 7.24£+01 u FH 03 518929001 8/10/2020 Cs-134 -2.67E+OO 3.25£+00 9.64£+00 u FH 03 518929001 8/10/2020 Cs-137 -1.68£-01 2.49£+00 8.06£+00 u FH 03 518929001 8/10/2020 Fe-59 -3.95£+00 6.35E+OO 1.89£+01 u FH 03 518929001 8/10/2020 1-131 -2.60E+OO 5.26E+OO 1.69£+01 u FH 03 518929001 8/10/2020 K-40 3.47E+03 2.32E+02 4.75£+01 FH 03 518929001 8/10/2020 La-140 -7.47E-Ol 3.17£+00 1.02£+01 u FH 03 518929001 8/10/2020 Mn-54 -5.93E-02 2.37E+OO 7.65£+00 u FH 03 518929001 8/10/2020 Nb-95 -l.02E+OO 2.80E+OO 8.80£+00 u FH 03 518929001 8/10/2020 Pb-212 -2.51E+OO 5.0IE+OO 1.54£+01 u FH 03 518929001 8/10/2020 Pb-214 -l.03E+Ol 6.38£+00 1.68£+01 u FH 03 518929001 8/10/2020 Ra-226 -4.25E-Ol 6.37E+OO 1.64£+01 u FH 03 518929001 8/10/2020 Ru-103 -1.34E+OO 2.21E+OO 6.84£+00 u FH 03 518929001 8/10/2020 Ru-106 -1.IOE+Ol 2.09£+01 6.48£+01 u FH 03 518929001 8/10/2020 Sb-124 -3.05E+OO 5.15£+00 1.55£+01 u FH 03 518929001 8/10/2020 Sb-125 4.93E+OO 5.0IE+OO 1.74£+01 u FH 03 518929001 8/10/2020 Se-75 3.29E+OO 2.75E+OO 9.41E+OO u FH 03 518929001 8/10/2020 Th-228 -2.51E+OO 5.0IE+OO 1.54£+01 u FH 03 518929001 8/10/2020 Th-230 -4.25E-Ol 6.37E+OO 1.64£+01 u FH 03 518929001 8/10/2020 Tl-208 5.08E-Ol 3.99£+00 7.18£+00 u FH 03 518929001 8/10/2020 Zn-65 3.94E+OO 7.20£+00 2.17£+01 u FH 03 518929001 8/10/2020 Zr-95 -7.15E+OO 4.69E+OO 1.19£+01 u FH 03 518929003 8/10/2020 Ac-228 -l.15E+Ol 9.12E+OO 2.82£+01 u FH 03 518929003 8/10/2020 Ag-108m 1.24E+OO l.51E+OO 5.04£+00 u FH 03 518929003 8/10/2020 Ag-1 lOm -5.64E+OO 3.40E+OO 8.97£+00 u FH 03 518929003 8/10/2020 Ba-140 l.83E+Ol l.23E+Ol 4.04£+01 u FH 03 518929003 8/10/2020 Be-7 -5.25E-Ol l.77E+Ol 5.64E+Ol u FH 03 518929003 8/10/2020 Bi-214 4.66E+OO 7.67E+OO l.31E+Ol u FH 03 518929003 8/10/2020 Ce-141 7.52E-Ol 5.99E+OO 9.96£+00 u FH 03 518929003 8/10/2020 Ce-144 4.07E+OO l.04E+Ol 3.58£+01 u FH 03 518929003 8/10/2020 Co-57 -1.1 IE+OO l.37E+OO 4.45£+00 u FH 03 518929003 8/10/2020 Co-58 7.15E-Ol 2.23E+OO 7.56£+00 u FH 03 518929003 8/10/2020 Co-60 l.30E+OO l.95E+OO 6.69£+00 u FH 03 518929003 8/10/2020 Cr-51 -6.46£+00 l.66E+Ol 5.29£+01 u FH 03 518929003 8/10/2020 Cs-134 -2.06E+OO 2.40E+OO 7.35£+00 u FH 03 518929003 8/10/2020 Cs-137 -2.33£+00 2.20E+OO 6.67E+OO u FH 03 518929003 8/10/2020 Fe-59 2.29E+OO 6.llE+OO 2.03E+Ol u FH 03 518929003 8/10/2020 1-131 1.70£+00 3.92E+OO 1.30£+01 u 183

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/kg) (pCi/kg) (pCi/kg)

FH 03 518929003 8/10/2020 K-40 2.73E+03 l.73E+02 5.18E+Ol FH 03 518929003 8/10/2020 La-140 -5.46E+OO 3.33E+OO 7.44E+OO u FH 03 518929003 8/10/2020 Mn-54 5.36E+OO 2.71E+OO 7.75E+OO u FH 03 518929003 8/10/2020 Nb-95 -4.51E+OO 2.46E+OO 6.35E+OO u FH 03 518929003 8/10/2020 Pb-212 -3.51E+OO 3.81E+OO l.13E+Ol u FH 03 518929003 8/10/2020 Pb-214 -8.41E-Ol 4.75E+OO l.34E+Ol u FH 03 518929003 8/10/2020 Ra-226 4.66E+OO 7.67E+OO 1.31E+Ol u FH 03 518929003 8/10/2020 Ru-103 l.79E+OO 2.35E+OO 7.02E+OO u FH 03 518929003 8/10/2020 Ru-106 6.56E+OO 2.0IE+Ol 6.15E+Ol u FH 03 518929003 8/10/2020 Sb-124 5.0IE+OO 3.61E+OO l.40E+Ol u FH 03 518929003 8/10/2020 Sb-125 9.94E+OO 6.78E+OO l.67E+Ol u FH 03 518929003 8/10/2020 Se-75 -3.47E+OO 2.43E+OO 7.00E+OO u FH 03 518929003 8/10/2020 Th-228 -3.51E+OO 3.81E+OO l.13E+Ol u FH 03 518929003 8/10/2020 Th-230 4.66E+OO 7.67E+OO 1.31E+Ol u FH 03 518929003 8/10/2020 Tl-208 l.48E+OO 2.03E+OO 6.72E+OO u FH 03 518929003 8/10/2020 Zn-65 3.74E+OO 5.37E+OO l.82E+Ol u FH 03 518929003 8/10/2020 Zr-95 -4.02E+OO 3.70E+OO l.IOE+Ol u FH 03 513410001 5/20/2020 Ac-228 -6.83E+OO 7.33E+OO 2.06E+Ol u FH 03 513410001 5/20/2020 Ag-108m l.25E+OO l.05E+OO 3.60E+OO u FH 03 513410001 5/20/2020 Ag-llOm 2.25E+OO 2.05E+OO 6.86E+OO u FH 03 513410001 5/20/2020 Ba-140 -2.72E-Ol 3.20E+Ol 9.71E+Ol u FH 03 513410001 5/20/2020 Be-7 l.32E+Ol l.51E+Ol 5.18E+Ol u FH 03 513410001 5/20/2020 Bi-214 5.78E+OO 5.75E+OO 8.06E+OO u FH 03 513410001 5/20/2020 Ce-141 -2.99E+OO 3.53E+OO l.09E+Ol u FH 03 513410001 5/20/2020 Ce-144 9.39E+OO 7.85E+OO 2.55E+Ol u FH 03 513410001 5/20/2020 Co-57 2.77E+OO 2.15E+OO 3.19E+OO u FH 03 513410001 5/20/2020 Co-58 -l.07E+OO l.94E+OO 5.71E+OO u FH 03 513410001 5/20/2020 Co-60 -4.90E-Ol 2.12E+OO 6.53E+OO u FH 03 513410001 5/20/2020 Cr-51 -l.68E+Ol 2.07E+Ol 6.77E+Ol u FH 03 513410001 5/20/2020 Cs-134 -2.92E+OO l.99E+OO 5.00E+OO u FH 03 513410001 5/20/2020 Cs-137 3.49E+OO 2.50E+OO 4.0IE+OO u FH 03 513410001 5/20/2020 Fe-59 -7.34E+OO 5.68E+OO l.56E+Ol u FH 03 513410001 5/20/2020 1-131 -7.67E+OO 2.00E+Ol 6.69E+Ol u FH 03 513410001 5/20/2020 K-40 3.40E+03 l.85E+02 3.91E+Ol FH 03 513410001 5/20/2020 La-140 -3.89E+OO 5.98E+OO l.76E+Ol u FH 03 513410001 5/20/2020 Mn-54 l.61E+OO l.63E+OO 5.41E+OO u FH 03 513410001 5/20/2020 Nb-95 -3.46E+OO 2.00E+OO 5.22E+OO u FH 03 513410001 5/20/2020 Pb-212 4.25E+OO 4.15E+OO 7.81E+OO u FH 03 513410001 5/20/2020 Pb-214 5.45E+OO 5.17E+OO 1.12E+Ol u FH 03 513410001 5/20/2020 Ra-226 5.78E+OO 5.75E+OO 8.06E+OO u FH 03 513410001 5/20/2020 Ru-103 -2.15E+OO 2.09E+OO 6.44E+OO u FH 03 513410001 5/20/2020 Ru-106 l.17E+Ol l.26E+Ol 4.28E+Ol u FH 03 513410001 5/20/2020 Sb-124 -l.14E-Ol 3.46E+OO l.14E+Ol u FH 03 513410001 5/20/2020 Sb-125 5.29E-Ol 2.98E+OO 1.02E+Ol u FH 03 513410001 5/20/2020 Se-75 -2.05E+OO l.92E+OO 5.52E+OO u FH 03 513410001 5/20/2020 Th-228 4.25E+OO 4.15E+OO 7.81E+OO u FH 03 513410001 5/20/2020 Th-230 5.78E+OO 5.75E+OO 8.06E+OO u FH 03 513410001 5/20/2020 Tl-208 l.92E+OO 2.47E+OO 4.76E+OO u FH 03 513410001 5/20/2020 Zn-65 3.20E+OO 3.74E+OO l.23E+Ol u FH 03 513410001 5/20/2020 Zr-95 3.03E+OO 3.16E+OO l.07E+Ol u 184

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/kg) (pCi/kg) (pCi/kg)

FH 03 529897001 11 /17 /2020 Ac-228 -4.56E+OO 1.18E+Ol 3.63E+OI u FH 03 529897001 11/17/2020 Ag-108m 2.24E+OO 1.39E+OO 4.97E+OO u FH 03 529897001 11117/2020 Ag-11 Om -3.63E+OO 3.25E+OO 8.96E+OO u FH 03 529897001 11/17/2020 Ba-140 -I .93E+OI 3.26E+Ol 9.65E+OI u FH 03 529897001 11/17/2020 Be-7 7.61E+OO 2.08E+Ol 7.22E+Ol u FH 03 529897001 11/17/2020 Bi-214 3.34E+OO 5.33E+OO l.79E+OI u FH 03 529897001 11/17/2020 Ce-141 -1.3 IE+OO 5.07E+OO l.48E+OI u FH 03 529897001 11/17/2020 Ce-144 4.18E+OO l.08E+Ol 3.62E+Ol u FH 03 529897001 11/17 /2020 Co-57 -7.11 E-0 I l.39E+OO 4.44E+OO u FH 03 529897001 11 /17 /2020 Co-58 -3.40E+OO 2.42E+OO 6.14E+OO u FH 03 529897001 11117 /2020 Co-60 1.16E+OO 2.54E+OO 8.94£+00 u FH 03 529897001 11 /17 /2020 Cr-51 -3.71E+Ol 3.21E+Ol 8.87E+Ol u FH 03 529897001 11/17/2020 Cs-134 5.IOE+OO 4.13E+OO 8.74E+OO u FH 03 529897001 11/17/2020 Cs-137 -2.75E-OI l.96E+OO 6.42E+OO u FH 03 529897001 11/17/2020 Fe-59 5.74E+OO 7.62E+OO 2.36E+Ol u FH 03 529897001 11/17/2020 1-131 l.55E+Ol 2.04E+OI 6.65E+OI u FH 03 529897001 11 /17 /2020 K-40 2.86E+03 l.94E+02 6.88E+OI FH 03 529897001 11/17/2020 La-140 l.02E+Ol 1.09E+Ol 4.0IE+Ol u FH 03 529897001 11/17/2020 Mn-54 -2.04E-Ol 2.39E+OO 7.36£+00 u FH 03 529897001 11 /17 /2020 Nb-95 5.1 lE-01 2.82E+OO 9.42E+OO u FH 03 529897001 11/17/2020 Pb-212 2.50E+OO 3.53E+OO 1.16£+01 u FH 03 529897001 11117/2020 Pb-214 l.14E+OI 6.65E+OO l.39E+Ol u FH 03 529897001 11/17/2020 Ra-226 3.34E+OO 5.33E+OO 1.79E+Ol u FH 03 529897001 11/17/2020 Ru-103 -8.13E-OI 2.62E+OO 8.65E+OO u FH 03 529897001 11117/2020 Ru-106 -4.07E+OI 2.0IE+Ol 4.65E+Ol u FH 03 529897001 11 /17 /2020 Sb-124 -5.21E+OO 5.44E+OO 1.61E+Ol u FH 03 529897001 11 II 7/2020 Sb-125 -2.60E+OO 4.38E+OO l.42E+OI u FH 03 529897001 11 /17 /2020 Se-75 -2.37E+OO 3.14E+OO 8.90E+OO u FH 03 529897001 11 /17 /2020 Th-228 2.50E+OO 3.53E+OO l.16E+Ol u FH 03 529897001 11/17/2020 Th-230 3.34E+OO 5.33E+OO l.79E+OI u FH 03 529897001 11/17/2020 Tl-208 -2.83E+OO 2.23E+OO 6.91E+OO u FH 03 529897001 11 /17 /2020 Zn-65 l.60E+OO 6.24E+OO 2.04E+Ol u FH 03 529897001 11/1 7/2020 Zr-95 -8.64E-01 4.81E+OO l.56E+Ol u FH 03 505302001 2/10/2020 Ac-228 -7.05E+OO l.23E+Ol 3.80E+Ol u FH 03 505302001 2/10/2020 Ag-108m 7.99E+OO 2.99E+OO 8.19E+OO u FH 03 505302001 2/10/2020 Ag-I !Om l.49E+OO 4.1 IE+OO 1.25E+OI u FH 03 505302001 2/10/2020 Ba-140 -1.53E+OI 2.1 IE+OI 6.36E+Ol u FH 03 505302001 2/10/2020 Be-7 3.21E+Ol 2.39E+Ol 7.97E+OI u FH 03 505302001 2/10/2020 Bi-214 -6.62E+OO 5.74E+OO l.53E+OI u FH 03 505302001 2/10/2020 Ce-141 -1.SIE+OO 4.42E+OO l.50E+OI u FH 03 505302001 2/10/2020 Ce-144 -7.69E-Ol l.42E+Ol 4.40E+OI u FH 03 505302001 2/10/2020 Co-57 -2.IOE-01 l.88E+OO 5.85E+OO u FH 03 505302001 2/10/2020 Co-58 4.18E+OO 2.86E+OO 9.97E+OO u FH 03 50530200 I 2/10/2020 Co-60 2.33E+OO 2.67E+OO 9.27E+OO u FH 03 505302001 2/10/2020 Cr-51 4.57E+OI 3.24E+OI 9.79E+Ol u FH 03 505302001 2/10/2020 Cs-134 -l.07E+OO 2.40E+OO 7.77E+OO u FH 03 505302001 2/10/2020 Cs-137 5.1 IE+OO 2.83E+OO 9.31E+OO u FH 03 505302001 2/10/2020 Fe-59 5.86E-01 6.59E+OO 2.19E+Ol u FH 03 505302001 211012020 1-131 -l.99E+OO 1.01 E+Ol 3.30E+OI u FH 03 50530200 I 2/10/2020 K-40 3.16E+03 2.13E+02 8.22E+OI 185

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/kg) (pCi/kg) (pCi/kg)

FH 03 505302001 2/10/2020 La-140 4.70E+OO 6.26E+OO 2.18E+Ol u FH 03 505302001 2/10/2020 Mn-54 2.60E+OO 2.51E+OO 8.76E+OO u FH 03 505302001 2/10/2020 Nb-95 -1.29E+OO 3.06E+OO 1.00E+Ol u FH 03 505302001 2/10/2020 Pb-212 1.04E+Ol 6.16E+OO l.52E+Ol u FH 03 505302001 2/10/2020 Pb-214 -1.06E+Ol 6.66E+OO 1.79E+Ol u FH 03 505302001 2/10/2020 Ra-226 -6.62E+OO 5.74E+OO l.53E+Ol u FH 03 505302001 2/10/2020 Ru-103 -2.57E+OO 3.03E+OO 9.08E+OO u FH 03 505302001 2/10/2020 Ru-106 -1.05E+Ol 2.47E+Ol 7.59E+Ol u FH 03 505302001 2/10/2020 Sb-124 6.54E-01 5.28E+OO 1.81E+Ol u FH 03 505302001 2/10/2020 Sb-125 2.46E+OO 7.16E+OO 2.37E+Ol u FH 03 505302001 2/10/2020 Se-75 -4.92E+OO 3.64E+OO 1.09E+Ol u FH 03 505302001 2/10/2020 Th-228 1.04E+Ol 6.16E+OO 1.52E+Ol u FH 03 505302001 2/10/2020 Th-230 -6.62E+OO 5.74E+OO 1.53E+Ol u FH 03 505302001 2/10/2020 Tl-208 1.26E+OO 2.80E+OO 8.91E+OO u FH 03 505302001 2/10/2020 Zn-65 -6.61E+OO 5.80E+OO l.65E+Ol u FH 03 505302001 2/10/2020 Zr-95 -6.69E+OO 4.87E+OO 1.39E+Ol u FH 06 513410003 5/27/2020 Ac-228 9.46E+OO 1.87E+Ol 3.17E+Ol u FH 06 513410003 5/27/2020 Ag-108m 2.19E+OO l.62E+OO 5.50E+OO u FH 06 513410003 5/27/2020 Ag-llOm -3.25E+OO 3.05E+OO 8.62E+OO u FH 06 513410003 5/27/2020 Ba-140 1.70E+Ol 2.70E+Ol 9.15E+Ol u FH 06 513410003 5/27/2020 Be-7 4.30E+OO 2.13E+Ol 7.17E+Ol u FH 06 513410003 5/27/2020 Bi-214 3.14E+OO 7.37E+OO 1.78E+Ol u FH 06 513410003 5/27/2020 Ce-141 6.94E-01 5.03E+OO 1.49E+Ol u FH 06 513410003 5/27/2020 Ce-144 -2.43E+Ol 1.36E+Ol 3.69E+Ol u FH 06 513410003 5/27/2020 Co-57 -7.03E-01 l.57E+OO 4.95E+OO u FH 06 513410003 5/27/2020 Co-58 -1.44E+OO 2.60E+OO 7.98E+OO u FH 06 513410003 5/27/2020 Co-60 2.42E+OO 2.69E+OO 8.63E+OO u FH 06 513410003 5/27/2020 Cr-51 -4.32E+OO 2.77E+Ol 9.39E+Ol u FH 06 513410003 5/27/2020 Cs-134 5.92E+OO 2.55E+OO 8.19E+OO u FH 06 513410003 5/27/2020 Cs-137 2.16E+OO 2.07E+OO 6.99E+OO u FH 06 513410003 5/27/2020 Fe-59 8.21E+OO 6.86E+OO 2.38E+Ol u FH 06 513410003 5/27/2020 I-131 -l.90E+Ol 1.88E+Ol 5.91E+Ol u FH 06 513410003 5/27/2020 K-40 3.31E+03 2.18E+02 4.71E+Ol FH 06 513410003 5/27/2020 La-140 -4.53E+OO 9.31E+OO 2.87E+Ol u FH 06 513410003 5/27/2020 Mn-54 2.lOE+OO 2.12E+OO 7.08E+OO u FH 06 513410003 5/27/2020 Nb-95 -3.39E-02 3.18E+OO 9.lOE+OO u FH 06 513410003 5/27/2020 Pb-212 -1.0lE+OO 4.66E+OO 1.34E+Ol u FH 06 513410003 5/27/2020 Pb-214 4.67E+OO 7.15E+OO 1.66E+Ol u FH 06 513410003 5/27/2020 Ra-226 3.14E+OO 7.37E+OO 1.78E+Ol u FH 06 513410003 5/27/2020 Ru-103 1.22E+OO 2.59E+OO 8.76E+OO u FH 06 513410003 5/27/2020 Ru-106 4.04E+Ol 2.33E+Ol 5.38E+Ol u FH 06 513410003 5/27/2020 Sb-124 3.61E+OO 5.45E+OO 1.90E+Ol u FH 06 513410003 5/27/2020 Sb-125 -5.40E-01 5.04E+OO l.68E+Ol u FH 06 513410003 5/27/2020 Se-75 3.87E+OO 2.68E+OO 9.13E+OO u FH 06 513410003 5/27/2020 Th-228 -1.0lE+OO 4.66E+OO 1.34E+Ol u FH 06 513410003 5/27/2020 Th-230 3.14E+OO 7.37E+OO 1.78E+Ol u FH 06 513410003 5/27/2020 Tl-208 -1.32E+OO 2.93E+OO 8.22E+OO u FH 06 513410003 5/27/2020 Zn-65 4.33E+OO 5.33E+OO 1.85E+Ol u FH 06 513410003 5/27/2020 Zr-95 -8.52E+OO 4.80E+OO 1.20E+Ol u 186

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/kg) (pCi/kg) (pCi/kg)

FH 53 505302002 2/19/2020 Ac-228 -6.05E+OO 9.17E+OO 2.76E+Ol u FH 53 505302002 2/19/2020 Ag-108m 8.36E-01 1.39E+OO 4.84E+OO u FH 53 505302002 2/19/2020 Ag-I I Om -1.21E+OO 2.57E+OO 7.85E+OO u FH 53 505302002 2/19/2020 Ba-140 -3.57E+OO 1.08E+Ol 3.51E+Ol u FH 53 505302002 2/19/2020 Be-7 -1.61E+OO 1.43E+Ol 4.78E+Ol u FH 53 505302002 2/19/2020 Bi-214 -4.29E-01 4.66E+OO 1.52E+Ol u FH 53 505302002 2/19/2020 Ce-141 -2.81E+OO 2.74E+OO 8.14E+OO u FH 53 505302002 2/19/2020 Ce-144 4.74E+OO 1.53E+Ol 2.88E+Ol u FH 53 505302002 2119/2020 Co-57 6.35E-01 1.25E+OO 4.14E+OO u FH 53 505302002 2/19/2020 Co-58 -1.26E+OO 2.03E+OO 6.17E+OO u FH 53 505302002 2/19/2020 Co-60 -2.97E+OO 2.65E+OO 7.71E+OO u FH 53 505302002 2/f9/2020 Cr-51 6.84E-01 1.55E+Ol 5.34E+Ol u FH 53 505302002 2/19/2020 Cs-134 2.1 lE+OO 2.45E+OO 8.30E+OO u FH 53 505302002 2/19/2020 Cs-137 O.OOE+OO 2.87E+OO 6.67E+OO u FH 53 505302002 2/19/2020 Fe-59 1.70E+OO 5.97E+OO 1.93E+Ol u FH 53 505302002 2/19/2020 I-131 4.35E-01 3.02E+OO 1.04E+Ol u FH 53 505302002 2/19/2020 K-40 3.42E+03 2.05E+02 5.14E+Ol FH 53 505302002 2/19/2020 La-140 6.93E-01 3.69E+OO 1.25E+Ol u FH 53 505302002 2/19/2020 Mn-54 -1.92E-01 1.91E+OO 6.13E+OO u FH 53 505302002 2/19/2020 Nb-95 1.42E+OO 2.37E+OO 7.91E+OO u FH 53 505302002 2/19/2020 Pb-212 3.26E+OO 4.83E+OO 9.72E+OO u FH 53 505302002 2/19/2020 Pb-214 -4.21E-01 4.lOE+OO 1.33E+Ol u FH 53 505302002 2/19/2020 Ra-226 -4.29E-01 4.66E+OO 1.52E+Ol u FH 53 505302002 2/19/2020 Ru-103 -8.89E-01 1.90E+OO 6.14E+OO u FH 53 505302002 2/19/2020 Ru-106 -1.06E+Ol l.31E+Ol 3.89E+Ol u FH 53 505302002 2/19/2020 Sb-124 3.63E+OO 3.41E+OO 1.30E+Ol u FH 53 505302002 2/19/2020 Sb-125 -8.75E-01 4.29E+OO 1.43E+Ol u FH 53 505302002 2/19/2020 Se-75 1.27E+OO 2.48E+OO 7.94E+OO u FH 53 505302002 2/19/2020 Th-228 3.26E+OO 4.83E+OO 9.72E+OO u FH 53 505302002 2/19/2020 Th-230 -4.29E-01 4.66E+OO 1.52E+Ol u FH 53 505302002 2/19/2020 Tl-208 -1.81E+OO 2.lOE+OO 6.30E+OO u FH 53 505302002 2/19/2020 Zn-65 1.67E+OO 5.82E+OO 1.88E+Ol u FH 53 505302002 2/19/2020 Zr-95 -4.39E+OO 3.80E+OO 1.07E+Ol u FH 53 530897001 12/18/2020 Ac-228 -2.0lE+Ol 2.06E+Ol 6.23E+Ol u FH 53 530897001 12/18/2020 Ag-108m 3.05E+OO 3.04E+OO 1.08E+Ol u FH 53 530897001 12/18/2020 Ag-llOm -1.95E+OO 7.76E+OO 1.62E+Ol u FH 53 530897001 12/18/2020 Ba-140 2.42E+Ol 2.07E+Ol 7.35E+Ol u FH 53 530897001 12/18/2020 Be-7 -2.55E+Ol 2.84E+Ol 8.58E+Ol u FH 53 530897001 12/18/2020 Bi-214 2.93E+Ol 1.39E+Ol 3.78E+Ol u FH 53 530897001 12/18/2020 Ce-141 1.26E+OO 5.48E+OO 1.71E+Ol u FH 53 530897001 12/18/2020 Ce-144 9.64E+OO 2.07E+Ol 7.00E+Ol u FH 53 530897001 12/18/2020 Co-57 -1.21E+OO 2.lOE+OO 6.74E+OO u FH 53 530897001 12/18/2020 Co-58 7.16E+OO 4.93E+OO l.72E+Ol u FH 53 530897001 12/18/2020 Co-60 4.45E+OO 5.06E+OO 1.81E+Ol u FH 53 530897001 12/18/2020 Cr-51 3.36E+Ol 3.55E+Ol 1.17E+02 u FH 53 530897001 12/18/2020 Cs-134 -4.77E+OO 4.77E+OO 1.33E+Ol u FH 53 530897001 12/18/2020 Cs-137 -3.55E+OO 4.69E+OO 1.42E+Ol u FH 53 530897001 12/18/2020 Fe-59 6.47E+OO 1.00E+Ol 3.55E+Ol u FH 53 530897001 12/18/2020 I-131 4.08E+OO 8.58E+OO 3.0lE+Ol u FH 53 530897001 12/18/2020 K-40 2.64E+03 2.36E+02 1.78E+02 187

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/kg) (pCi/kg) (pCi/kg)

FH 53 530897001 12/18/2020 La-140 1.43E+OO 7.45E+OO 2.51E+Ol u FH 53 530897001 12/18/2020 Mn-54 5.33E+OO 5.14E+OO 1.62E+Ol u FH 53 530897001 12/18/2020 Nb-95 4.96E+OO 4.19E+OO 1.47E+Ol u FH 53 530897001 12/18/2020 Pb-212 -1.75E+Ol 8.35E+OO 2.00E+Ol u FH 53 530897001 12/18/2020 Pb-214 8.37E+OO 1.03E+Ol 3.16E+Ol u FH 53 530897001 12/18/2020 Ra-226 2.93E+Ol l.39E+Ol 3.78E+Ol u FH 53 530897001 12/18/2020 Ru-103 1.18E+OO 4.19E+OO 1.44E+Ol u FH 53 530897001 12/18/2020 Ru-106 -3.89E+OO 4.16E+Ol l.36E+02 u FH 53 530897001 12/18/2020 Sb-124 -2.16E+Ol 1.12E+Ol 1.57E+Ol u FH 53 530897001 12/18/2020 Sb-125 1.00E+Ol 1.0IE+Ol 3.55E+Ol u FH 53 530897001 12/18/2020 Se-75 -1.95E+OO 4.92E+OO 1.52E+Ol u FH 53 530897001 12/18/2020 Th-228 -1.75E+Ol 8.35E+OO 2.00E+Ol u FH 53 530897001 12/18/2020 Th-230 2.93E+Ol l.39E+Ol 3.78E+Ol u FH 53 530897001 12/18/2020 Tl-208 -6.62E+OO 6.00E+OO 1.73E+Ol u FH 53 530897001 12/18/2020 Zn-65 6.llE+OO 9.94E+OO 3.51E+Ol u FH 53 530897001 12/18/2020 Zr-95 3.83E+OO 7.82E+OO 2.65E+Ol u FH 53 511590001 5/13/2020 Ac-228 1.82E+Ol 1.IIE+Ol 2.0IE+Ol u FH 53 511590001 5/13/2020 Ag-108m -2.04E-Ol 1.44E+OO 4.79E+OO u FH 53 511590001 5/13/2020 Ag-llOm 2.47E+OO 2.50E+OO 8.32E+OO u FH 53 511590001 5/13/2020 Ba-140 5.35E+OO 8.82E+OO 2.99E+Ol u FH 53 511590001 5113/2020 Be-7 7.47E+OO 1.42E+Ol 4.81E+Ol u FH 53 511590001 5113/2020 Bi-214 -2.45E+OO 4.84E+OO l.37E+Ol u FH 53 511590001 5/13/2020 Ce-141 2.66E+OO 3.04E+OO 9.79E+OO u FH 53 511590001 5/13/2020 Ce-144 6.68E+OO 1.05E+Ol 3.41E+Ol u FH 53 511590001 5113/2020 Co-57 1.00E-01 l.33E+OO 4.29E+OO u FH 53 511590001 5113/2020 Co-58 4.07E-01 l.63E+OO 5.33E+OO u FH 53 511590001 5113/2020 Co-60 -2.48E+OO 2.44E+OO 6.16E+OO u FH 53 511590001 5113/2020 Cr-51 -2.50E+Ol 1.75E+Ol 4.85E+Ol u FH 53 511590001 5/13/2020 Cs-134 -2.lOE-01 1.89E+OO 6.03E+OO u FH 53 511590001 5/13/2020 Cs-137 O.OOE+OO 2.31E+OO 5.16E+OO u FH 53 511590001 5113/2020 Fe-59 1.83E+OO 4.74E+OO 1.63E+Ol u FH 53 511590001 5/13/2020 1-131 3.54E+OO 3.40E+OO l.16E+Ol u FH 53 511590001 5/13/2020 K-40 3.43E+03 2.17E+02 5.42E+Ol FH 53 511590001 5/13/2020 La-140 -3.60E+OO 2.84E+OO 7.42E+OO u FH 53 511590001 5/13/2020 Mn-54 -1.27E+OO 1.97E+OO 6.0IE+OO u FH 53 511590001 5113/2020 Nb-95 1.25E+OO 1.94E+OO 6.45E+OO u FH 53 511590001 5113/2020 Pb-212 -6.21E+OO 4.03E+OO 1.02E+Ol u FH 53 511590001 5113/2020 Pb-214 5.87E+OO 7.17E+OO 1.35E+Ol u FH 53 511590001 5/13/2020 Ra-226 -2.45E+OO 4.84E+OO l.37E+Ol u FH 53 511590001 5113/2020 Ru-103 1.21E+OO 1.63E+OO 5.53E+OO u FH 53 511590001 5113/2020 Ru-106 -l.36E+Ol 1.62E+Ol 4.97E+Ol u FH 53 511590001 5/13/2020 Sb-124 -2.llE-01 3.74E+OO 1.17E+Ol u FH 53 511590001 5113/2020 Sb-125 -4.70E-01 4.05E+OO l.35E+Ol u FH 53 511590001 5113/2020 Se-75 3.59E-Ol 2.05E+OO 7.07E+OO u FH 53 511590001 5113/2020 Th-228 -6.21E+OO 4.03E+OO 1.02E+Ol u FH 53 511590001 5113/2020 Th-230 -2.45E+OO 4.84E+OO l.37E+Ol u FH 53 511590001 5/13/2020 Tl-208 -2.59E+OO 2.32E+OO 6.41E+OO u FH 53 511590001 5/13/2020 Zn-65 4.12E+OO 4.95E+OO 1.71E+Ol u FH 53 511590001 5113/2020 Zr-95 5.71E+OO 5.03E+OO 1.09E+Ol u 188

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/kg) (pCi/kg) (pCi/kg)

FH 53 518929002 8/1112020 Ac-228 9.32E-OI l.05E+OI 3.19E+Ol u FH 53 518929002 8/11/2020 Ag-108m -2.87E+OO 1.71 E+OO 4.61E+OO u FH 53 518929002 8/11 /2020 Ag- II Om -1.26E+OO 3.33E+OO 1.02E+OI u FH 53 518929002 8/11 /2020 Ba-140 O.OOE+OO 1.92E+OI 3.91E+Ol u FH 53 518929002 8/11 /2020 Be- 7 -2.52E+Ol l .85E+Ol 5.28E+OI u FH 53 518929002 8/11 /2020 Bi-214 -2.29E+OO 4.50E+OO l.41E+Ol u FH 53 518929002 8/1112020 Ce-141 l.56E-OI 3.0IE+OO 9.26E+OO u FH 53 518929002 8/11 /2020 Ce-144 2.92E+OO l.12E+Ol 3.65E+OI u FH 53 518929002 8/1112020 Co-57 l.18E+OO I .43E+OO 4.70E+OO u FH 53 518929002 8/11/2020 Co-58 -2.43E+OO 2.16E+OO 5.88E+OO u FH 53 518929002 8/11 /2020 Co-60 3.95E+OO 2.44E+OO 8.81E+OO u FH 53 518929002 8/11/2020 Cr-51 3.41E+OI 2.35E+OI 5.45E+Ol u FH 53 518929002 8/11/2020 Cs-134 l.22E+OO 2.44E+OO 8.13E+OO u FH 53 518929002 8/11/2020 Cs-13 7 6.72E+OO 2.79E+OO 8.99E+OO u FH 53 518929002 8/11/2020 Fe-59 -l.27E+OO 5.46E+OO l.58E+Ol u FH 53 518929002 8/1112020 1-131 5.38E+OO 3.61E+OO l.25E+Ol u FH 53 518929002 8/1112020 K-40 3.50E+03 2.25E+02 5.39E+OI FH 53 518929002 8/1 I /2020 La-140 7. I 9E-02 3.28E+OO 1.08E+Ol u FH 53 518929002 8/1112020 Mn-54 -3.17E+OO 2.22E+OO 5.28E+OO u FH 53 518929002 8/1112020 Nb-95 9.13E-OI 2.18E+OO 7.23E+OO u FH 53 518929002 8/1112020 Pb-212 9.92E+OO 6.41E+OO l.84E+Ol u FH 53 518929002 8/1 1/2020 Pb-214 4.34E-01 4.35E+OO l .38E+Ol u FH 53 518929002 8/1112020 Ra-226 -2.29E+OO 4.50E+OO l.41E+Ol u FH 53 518929002 8/1112020 Ru-103 -2.82E-02 l.79E+OO 5.92E+OO u FH 53 518929002 8/11/2020 Ru-106 1.1 IE+Ol l.62E+Ol 5.53E+OI u FH 53 518929002 8/11/2020 Sb-124 3.02E+OO 3.67E+OO l.36E+Ol u FH 53 518929002 8/1 I /2020 Sb-125 -l.12E+OO 4.94E+OO l.63E+Ol u FH 53 518929002 8/1112020 Se-75 2.49E-OI 2.17E+OO 7.50E+OO u FH 53 518929002 8/1112020 Th-228 9.92E+OO 6.41E+OO l.84E+OI u FH 53 518929002 8/11/2020 Th-230 -2.29E+OO 4.50E+OO 1.41E+Ol u FH 53 518929002 8/11 /2020 Tl-208 4.20E+OO 4.07E+OO 6.28E+OO u FH 53 518929002 8/1112020 Zn-65 l.30E+OO 5.40E+OO l.85E+Ol u FH 53 518929002 8/1112020 Zr-95 3.00E+OO 4.09E+OO l .38E+Ol u 189

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/kg) (pCi/kg) (pCi/kg)

HA 04 511606001 5/14/2020 Ac-228 l.97E+Ol l.64E+Ol 4.88E+Ol u HA 04 511606001 5/14/2020 Ag-108m -l.83E+OO 3.06E+OO 8.29E+OO u HA 04 511606001 5/14/2020 Ag-llOm -l.78E+OO 4.42E+OO l.45E+Ol u HA 04 511606001 5/14/2020 Ba-140 3.72E+Ol 3.15E+Ol 4.06E+Ol u HA 04 511606001 5/14/2020 Be-7 -4.21E+Ol 3.24E+Ol 8.45E+Ol u HA 04 511606001 5/14/2020 Bi-214 -4.97E+OO 8.37E+OO 2.37E+Ol u HA 04 511606001 5/14/2020 Ce-141 2.26E+OO 4.85E+OO 1.52E+Ol u HA 04 511606001 5/14/2020 Ce-144 -5.13E+OO l.62E+Ol 5.26E+Ol u HA 04 511606001 5/14/2020 Co-57 l.OlE+OO 2.23E+OO 6.50E+OO u HA 04 511606001 5/14/2020 Co-58 4.27E+OO 2.79E+OO 9.84E+OO u HA 04 511606001 5/14/2020 Co-60 2.41E+OO 3.78E+OO l.29E+Ol u HA 04 511606001 5/14/2020 Cr-51 3.90E+OO 3.39E+Ol 9.79E+Ol u HA 04 511606001 5/14/2020 Cs-134 6.50E+OO 3.70E+OO l.27E+Ol u HA 04 511606001 5/14/2020 Cs-137 2.80E+OO 3.76E+OO l.24E+Ol u HA 04 511606001 5/14/2020 Fe-59 -l.04E+Ol 7.25E+OO 2.0lE+Ol u HA 04 511606001 5/14/2020 I-131 -4.86E+OO 5.88E+OO l.84E+Ol u HA 04 511606001 5/14/2020 K-40 2.31E+03 l.63E+02 8.lOE+Ol HA 04 511606001 5/14/2020 La-140 l.lOE+OO 6.63E+OO 2.18E+Ol u HA 04 511606001 5/14/2020 Mn-54 -3.67E-01 3.24E+OO l.09E+Ol u HA 04 511606001 5/14/2020 Nb-95 -3.21E-01 3.57E+OO 1.12E+Ol u HA 04 511606001 5/14/2020 Pb-212 -1.39E+Ol 7.67E+OO l.89E+Ol u HA 04 511606001 5/14/2020 Pb-214 l.14E+Ol 8.67E+OO 2.51E+Ol u HA 04 511606001 5/14/2020 Ra-226 -4.97E+OO 8.37E+OO 2.37E+Ol u HA 04 511606001 5/14/2020 Ru-103 4.90E+OO 3.38E+OO 1.12E+Ol u HA 04 511606001 5/14/2020 Ru-106 9.88E+OO 2.79E+Ol 9.14E+Ol u HA 04 511606001 5/14/2020 Sb-124 7.99E+OO 7.26E+OO 2.57E+Ol u HA 04 511606001 5/14/2020 Sb-125 3.78E+OO 7.72E+OO 2.33E+Ol u HA 04 511606001 5/14/2020 Se-75 -2.15E+OO 3.59E+OO l.16E+Ol u HA 04 511606001 5/14/2020 Th-228 -1.39E+Ol 7.67E+OO l.89E+Ol u HA 04 511606001 5/14/2020 Th-230 -4.97E+OO 8.37E+OO 2.37E+Ol u HA 04 511606001 5/14/2020 Tl-208 -3.60E+OO 4.48E+OO 1.20E+Ol u HA 04 511606001 5/14/2020 Zn-65 6.55E+OO 7.68E+OO 2.65E+Ol u HA 04 511606001 5/14/2020 Zr-95 7.09E+OO 5.53E+OO l.85E+Ol u HA 04 528387001 11/19/2020 Ac-228 -5.0lE+OO 7.35E+OO 2.15E+Ol u HA 04 528387001 11119/2020 Ag-108m -5.86E-01 1.03E+OO 3.35E+OO u HA 04 528387001 11119/2020 Ag-1 lOm 2.26E+OO 2.04E+OO 6.86E+OO u HA 04 528387001 11119/2020 Ba-140 O.OOE+OO 2.53E+Ol 3.59E+Ol u HA 04 528387001 11119/2020 Be-7 -3.33E-01 l.25E+Ol 4.19E+OI u HA 04 528387001 11119/2020 Bi-214 O.OOE+OO 7.47E+OO 1.30E+Ol u HA 04 528387001 11119/2020 Ce-141 -8.67E+OO 3.52E+OO 6.76E+OO u HA 04 528387001 11119/2020 Ce-144 3.30E+OO 7.61E+OO 2.48E+Ol u HA 04 528387001 11119/2020 Co-57 l.15E+OO 9.94E-01 3.24E+OO u HA 04 528387001 11119/2020 Co-58 9.38E-01 1.54E+OO 5.13E+OO u HA 04 528387001 11/19/2020 Co-60 -3.79E-01 l.57E+OO 5.15E+OO u HA 04 528387001 11/19/2020 Cr-51 -l.54E+Ol l.21E+Ol 3.73E+Ol u HA 04 528387001 11/19/2020 Cs-134 -2.12E+OO l.40E+OO 3.65E+OO u HA 04 528387001 11/19/2020 Cs-137 l.80E+OO l.41E+OO 4.79E+OO u HA 04 528387001 11119/2020 Fe-59 5.64E-01 3.75E+OO 1.20E+Ol u 190

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/kg) (pCi/kg) (pCi/kg)

HA 04 528387001 11/19/2020 l-131 2.34E+OO 3.64E+OO l.26E+01 u HA 04 528387001 11/19/2020 K-40 l.98E+03 l.19E+02 5.98E+Ol HA 04 528387001 11/19/2020 La-140 -7.72E+OO 3.13E+OO 3.86E+OO u HA 04 528387001 11 /19/2020 Mn-54 8.30E-02 1.46E+OO 4.73E+OO u HA 04 528387001 11 /19/2020 Nb-95 3.22E-Ol l.62E+OO 5.33E+OO u HA 04 528387001 11/19/2020 Pb-212 2.49E+OO 3.94E+OO 8.63E+OO u HA 04 528387001 11/19/2020 Pb-214 3.92E+OO 5.74E+OO l.13E+Ol u HA 04 528387001 11/19/2020 Ra-226 O.OOE+OO 7.47E+OO 1.30E+01 u HA 04 528387001 1111912020 Ru-103 2.02E-01 l.60E+OO 5.39E+OO u HA 04 528387001 11 /19/2020 Ru-106 -2.05E+Ol 1.30E+Ol 3.57E+01 u HA 04 528387001 11/19/2020 Sb-124 -3.88E+OO 3.16E+OO 8.18E+OO u HA 04 528387001 l 1/19/2020 Sb-125 2.69E+OO 3.47E+OO l.19E+Ol u HA 04 528387001 11/19/2020 Se-75 -7.57E-01 1.82E+OO 5.55E+OO u HA 04 528387001 11/19/2020 Th-228 2.49E+OO 3.94E+OO 8.63E+OO u HA 04 528387001 11/19/2020 Th-230 O.OOE+OO 7.47E+OO 1.30E+01 u HA 04 528387001 11/19/2020 Tl-208 1. 71 E-01 2.34E+OO 4.23E+OO u HA 04 528387001 1111912020 Zn-65 l.04E+OO 3.80E+OO 1.31E+01 u HA 04 528387001 1111912020 Zr-95 l.16E+OO 2.98E+OO 9.90E+OO u HA 54 511606002 5/15/2020 Ac-228 8.67E+Ol 2.45E+01 4.25E+Ol HA 54 511606002 5/15/2020 Ag-108m 2.24E+OO 3.35E+OO 1.13E+Ol u HA 54 511606002 511512020 Ag-11 Om -l.90E+OO 4.74E+OO 1.55E+01 u HA 54 511606002 5/15/2020 Ba-140 l.45E+Ol 2.45E+01 6.31E+Ol u HA 54 511606002 5/15/2020 Be-7 3.67E+01 3.50E+Ol 1.04E+02 u HA 54 511606002 5/15/2020 Bi-214 -3.23E+OO l.14E+Ol 3.13E+Ol u HA 54 511606002 5/15/2020 Ce-141 5.06E+OO l.04E+Ol l.96E+Ol u HA 54 511606002 511512020 Ce-144 -4.77E-01 2.15E+01 7.27£+01 u HA 54 511606002 5/15/2020 Co-57 -3.20E-Ol 2.77E+OO 9.42E+OO u HA 54 511606002 511512020 Co-58 5.81E+OO 3.69E+OO 1.23£+01 u HA 54 511606002 511512020 Co-60 -2.60E+OO 3.53E+OO l.12E+Ol u HA 54 511606002 511512020 Cr-51 1.32E+01 3.60E+01 1.16£+02 u HA 54 511606002 5/15/2020 Cs-134 5.04E+OO 6.04E+OO 1.35£+01 u HA 54 511606002 5/15/2020 Cs-13 7 9. 72E-Ol 3.96E+OO l.29E+Ol u HA 54 511606002 511512020 Fe-59 -3.71E-Ol 7.42E+OO 2.42E+Ol u HA 54 511606002 511512020 I-131 -2.06E+OO 6.43E+OO 2.16E+Ol u HA 54 511606002 511512020 K-40 2.60E+03 1.82E+02 1.11£+02 HA 54 511606002 511512020 La-140 -2.27E+OO 5.33E+OO 1.70E+Ol u HA 54 511606002 511512020 Mn-54 7.50E-Ol 3.54E+OO 1.19£+01 u HA 54 511606002 511512020 Nb-95 4.85E+OO 3.83E+OO l.29E+Ol u HA 54 511606002 511512020 Pb-212 -9.51E-Ol 9.47E+OO 2.70£+01 u HA 54 511606002 511512020 Pb-214 -9.24E+OO l.14E+Ol 3.09E+Ol u HA 54 511606002 511512020 Ra-226 -3.23E+OO l.14E+01 3.13E+Ol u HA 54 511606002 5/15/2020 Ru-103 2.68E+OO 3.70E+OO 1.24£+01 u HA 54 511606002 5/15/2020 Ru-106 l.86E+Ol 3.33E+Ol 1.09£+02 u HA 54 511606002 511512020 Sb-124 -9.19E+OO 8.69E+OO 2.56E+Ol u HA 54 511606002 5115/2020 Sb-125 -5.95E+OO 9.76E+OO 3.18£+01 u HA 54 511606002 511512020 Se-75 -7.65E-Ol 5.lOE+OO 1.64E+Ol u HA 54 511606002 511512020 Th-228 -9.51E-Ol 9.47E+OO 2.70£+01 u HA 54 511606002 5115/2020 Th-230 -3.23E+OO l.14E+01 3.13£+01 u HA 54 511606002 5115/2020 Tl-208 2.10E+01 8.02E+OO l.16E+Ol UI HA 54 511606002 511512020 Zn-65 -1.66E+OO 8.36E+OO 2.70£+01 u 191

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/kg) (pCi/kg) (pCi/kg)

HA 54 511606002 5/15/2020 Zr-95 -8.69E+OO 6.79E+OO 2.08E+Ol u HA 54 528387002 11/21/2020 Ac-228 l.OIE+Ol l.45E+Ol 4.59E+Ol u HA 54 528387002 11/21/2020 Ag-108m -l.55E+OO 2.13E+OO 6.88E+OO u HA 54 528387002 11/21/2020 Ag-llOm 2.35E+OO 3.49E+OO l.18E+Ol u HA 54 528387002 11/21/2020 Ba-140 -l.88E+Ol l.45E+Ol 4.17E+Ol u HA 54 528387002 11/21/2020 Be-7 2.06E+Ol 2.26E+Ol 7.82E+Ol u HA 54 528387002 11/21/2020 Bi-214 l.15E+Ol l.26E+Ol l.54E+Ol u HA 54 528387002 11/21/2020 Ce-141 -3.06E+OO 3.91E+OO l.24E+Ol u HA 54 528387002 11/21/2020 Ce-144 -l.15E+Ol l.30E+Ol 4.llE+Ol u HA 54 528387002 11/21/2020 Co-57 -9.95E-Ol l.67E+OO 5.41E+OO u HA 54 528387002 11/21/2020 Co-58 -3.00E+OO 2.81E+OO 7.44E+OO u HA 54 528387002 11/21/2020 Co-60 -6.50E-Ol 2.80E+OO 7.90E+OO u HA 54 528387002 11/21/2020 Cr-51 -1.19E+Ol 2.49E+Ol 7.58E+Ol u HA 54 528387002 11/21/2020 Cs-134 7.63E-Ol 2.61E+OO 8.68E+OO u HA 54 528387002 11/21/2020 Cs-137 l.38E+OO 2.40E+OO 8.18E+OO u HA 54 528387002 11/21/2020 Fe-59 -9.93E+OO 6.46E+OO l.76E+Ol u HA 54 528387002 11/21/2020 I-131 -2.61E+OO 6.81E+OO l.96E+Ol u HA 54 528387002 11/21/2020 K-40 l.89E+03 l.50E+02 7.92E+Ol HA 54 528387002 11/21/2020 La-140 4.26E+OO 4.84E+OO l.63E+Ol u HA 54 528387002 11/21/2020 Mn-54 5.57E+OO 3.00E+OO 1.0IE+Ol u HA 54 528387002 11121/2020 Nb-95 -6.35E+OO 3.47E+OO 8.IOE+OO u HA 54 528387002 11/21/2020 Pb-212 3.25E+OO 5.90E+OO l.58E+Ol u HA 54 528387002 11/21/2020 Pb-214 5.61E-Ol l.33E+Ol l.99E+Ol u HA 54 528387002 11/21/2020 Ra-226 l.15E+Ol l.26E+Ol l.54E+Ol u HA 54 528387002 11/21/2020 Ru-103 2.82E+OO 2.69E+OO 9.31E+OO u HA 54 528387002 11/21/2020 Ru-106 l.94E+Ol 2.0IE+Ol 6.95E+Ol u HA 54 528387002 11/21/2020 Sb-124 4.34E+OO 5.87E+OO 2.IOE+Ol u HA 54 528387002 11/21/2020 Sb-125 -5.35E+OO 6.41E+OO 2.05E+Ol u HA 54 528387002 11/21/2020 Se-75 -3.74E-Ol 3.40E+OO 9.75E+OO u HA 54 528387002 11/21/2020 Th-228 3.25E+OO 5.90E+OO l.58E+Ol u HA 54 528387002 11/21/2020 Th-230 l.15E+Ol l.26E+Ol l.54E+Ol u HA 54 528387002 11/21/2020 Tl-208 O.OOE+OO 5.25E+OO 6.70E+OO u HA 54 528387002 11/21/2020 Zn-65 -5.86E+OO 5.77E+OO l.73E+Ol u HA 54 528387002 11/21/2020 Zr-95 -l.57E+OO 4.llE+OO l.29E+Ol u 192

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/kg) (pCi/kg) (pCi/kg)

MU 06 511611001 5/14/2020 Ac-228 3.28E+OO l.33E+Ol 2.21E+Ol u MU 06 511611001 5/14/2020 Ag-108m l.22E+OO l.63E+OO 5.35E+OO u MU 06 511611001 5/14/2020 Ag-llOm -3.26E-Ol 2.59E+OO 8.45E+OO u MU 06 511611001 5/14/2020 Ba-140 7.49E+OO l.18E+Ol 3.84E+Ol u MU 06 511611001 5/14/2020 Be-7 4.42E+Ol 2.75E+Ol 5.18E+Ol u MU 06 511611001 5/14/2020 Bi-214 -8.39E+OO 4.88E+OO l.25E+Ol u MU 06 511611001 5/14/2020 Ce-141 -l.37E+Ol 4.92E+OO l.OIE+Ol u MU 06 511611001 5/14/2020 Ce-144 -l.09E+Ol l.05E+Ol 3.39E+Ol u MU 06 511611001 5/14/2020 Co-57 2.55E+OO l.95E+OO 4.34E+OO u MU 06 511611001 5/14/2020 Co-58 -l.67E+OO l.80E+OO 5.43E+OO u MU 06 511611001 5114/2020 Co-60 -6.32E-Ol l.75E+OO 5.69E+OO u MU 06 511611001 5/14/2020 Cr-51 -l.55E+Ol l.85E+Ol 5.74E+Ol u MU 06 511611001 5/14/2020 Cs-134 -4.46E-Ol 2.07E+OO 6.54E+OO u MU 06 511611001 5/14/2020 Cs-137 4.38E-Ol l.65E+OO 5.62E+OO u MU 06 511611001 5/14/2020 Fe-59 5.27E+OO 5.65E+OO l.45E+Ol u MU 06 511611001 5/14/2020 I-131 -1.llE+OO 4.94E+OO l.59E+Ol u MU 06 511611001 5/14/2020 K-40 l.34E+03 l.03E+02 6.37E+Ol MU 06 511611001 5/14/2020 La-140 -l.06E+Ol 5.09E+OO l.13E+Ol u MU 06 511611001 5/14/2020 Mn-54 -l.22E+OO l.74E+OO 5.41E+OO u MU 06 511611001 5/14/2020 Nb-95 4.22E+OO l.99E+OO 6.61E+OO u MU 06 511611001 5/14/2020 Pb-212 -5.65E+OO 4.45E+OO l.25E+Ol u MU 06 511611001 5/14/2020 Pb-214 l.75E+OO 6.58E+OO l.47E+Ol u MU 06 511611001 5/14/2020 Ra-226 -8.39E+OO 4.88E+OO l.25E+Ol u MU 06 511611001 5/14/2020 Ru-103 -l.04E+OO 2.43E+OO 6.63E+OO u MU 06 511611001 5/14/2020 Ru-106 9.84E+OO l.50E+Ol 5.19E+Ol u MU 06 511611001 5/14/2020 Sb-124 4.77E+OO 4.03E+OO l.44E+Ol u MU 06 511611001 5114/2020 Sb-125 -4.53E+OO 5.04E+OO l.52E+Ol u MU 06 511611001 5/14/2020 Se-75 3.34E+OO 3.16E+OO 7.75E+OO u MU 06 511611001 5/14/2020 Th-228 -5.65E+OO 4.45E+OO l.25E+Ol u MU 06 511611001 5/14/2020 Th-230 -8.39E+OO 4.88E+OO l.25E+Ol u MU 06 511611001 5/14/2020 Tl-208 l.69E+OO 4.83E+OO 5.55E+OO u MU 06 511611001 5/14/2020 Zn-65 -5.96E+OO 4.88E+OO l.38E+Ol u MU 06 511611001 5/14/2020 Zr-95 -9.81E-Ol 3.45E+OO l.13E+Ol u MU 06 529883001 12/9/2020 Ac-228 9.62E+OO l.06E+Ol 2.28E+Ol u MU 06 529883001 12/9/2020 Ag-108m l.83E+OO l.13E+OO 3.75E+OO u MU 06 529883001 12/9/2020 Ag-1 IOm -l.15E+OO l.65E+OO 5.24E+OO u MU 06 529883001 12/9/2020 Ba-140 -l.17E+Ol 7.05E+OO l.89E+Ol u MU 06 529883001 12/9/2020 Be-7 2.66E+Ol l.29E+Ol 4.IOE+Ol u MU 06 529883001 12/9/2020 Bi-214 l.16E+Ol 5.60E+OO l.16E+Ol u MU 06 529883001 12/9/2020 Ce-141 3.56E+OO 3.41E+OO 6.09E+OO u MU 06 529883001 12/9/2020 Ce-144 4.59E+OO 7.70E+OO 2.44E+Ol u MU 06 529883001 12/9/2020 Co-57 6.23E-01 9.84E-Ol 3.12E+OO u MU 06 529883001 12/9/2020 Co-58 -7.05E-Ol 1.40E+OO 4.22E+OO u MU 06 529883001 12/9/2020 Co-60 l.33E+OO l.57E+OO 5.40E+OO u MU 06 529883001 12/9/2020 Cr-51 -l.46E+Ol l.13E+Ol 3.39E+Ol u MU 06 529883001 12/9/2020 Cs-134 -2.44E-Ol l.52E+OO 4.77E+OO u MU 06 529883001 12/9/2020 Cs-137 2.47E+OO l.87E+OO 3.58E+OO u MU 06 529883001 12/9/2020 Fe-59 -l.13E+OO 2.98E+OO 9.68E+OO u MU 06 529883001 12/9/2020 1-131 -9.54E-Ol l.91E+OO 6.15E+OO u MU 06 529883001 12/9/2020 K-40 l.07E+03 8.16E+Ol 4.92E+Ol 193

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/kg) (pCi/kg) (pCi/kg)

MU 06 529883001 12/9/2020 La-140 3.98E+OO 2.06E+OO 7.40E+OO u MU 06 529883001 12/9/2020 Mn-54 1.82£-01 1.25E+OO 4.30E+OO u MU 06 529883001 12/9/2020 Nb-95 -4.48£-02 1.40E+OO 4.43E+OO u MU 06 529883001 12/9/2020 Pb-212 2.68E+OO 3.81E+OO 8.92E+OO u MU 06 529883001 12/9/2020 Pb-214 -1.85E+OO 3.29E+OO 1.03E+Ol u MU 06 529883001 12/9/2020 Ra-226 l.16E+Ol 5.60E+OO 1.16E+Ol u MU 06 529883001 12/9/2020 Ru-103 6.00E-01 1.15E+OO 3.83E+OO u MU 06 529883001 12/9/2020 Ru-106 1.29E+Ol 1.26E+Ol 4.19E+Ol u MU 06 529883001 12/9/2020 Sb-124 l.05E+OO 2.97E+OO 9.99E+OO u MU 06 529883001 12/9/2020 Sb-125 -5.00E+OO 3.27E+OO 9.13E+OO u MU 06 529883001 12/9/2020 Se-75 -1.75E+OO 1.56E+OO 4.85E+OO u MU 06 529883001 12/9/2020 Th-228 2.68E+OO 3.81E+OO 8.92E+OO u MU 06 529883001 12/9/2020 Th-230 1.16E+Ol 5.60E+OO l.16E+Ol u MU 06 529883001 12/9/2020 Tl-208 2.65E+OO 2.50E+OO 4.llE+OO u MU 06 529883001 12/9/2020 Zn-65 2.34£-01 2.85E+OO 9.55E+OO u MU 06 529883001 12/9/2020 Zr-95 -1.19£-01 2.75E+OO 7.73E+OO u MU 09 511593001 5/1112020 Ac-228 -4.76E+Ol 2.33E+Ol 5.06E+Ol u MU 09 511593001 5/1112020 Ag-108m 1.74E+OO 2.58E+OO 9.07E+OO u MU 09 511593001 5/1112020 Ag-llOm 4.87£-01 5.67E+OO 1.83E+Ol u MU 09 511593001 5/1112020 Ba-140 1.39E+Ol 1.87E+Ol 6.54E+Ol u MU 09 511593001 5/1112020 Be-7 1.68E+Ol 2.89E+Ol 1.01E+02 u MU 09 511593001 5/1112020 Bi-214 8.llE+OO 8.78E+OO 2.82E+Ol u MU 09 511593001 5/1112020 Ce-141 9.74£-02 3.04E+OO 1.04E+Ol u MU 09 511593001 5/1112020 Ce-144 8.94E+OO 1.13E+Ol 3.96E+Ol u MU 09 511593001 511112020 Co-57 2.37E+OO 1.44E+OO 4.93E+OO u MU 09 511593001 5/1112020 Co-58 1.70E+OO 3.44E+OO l.16E+Ol u MU 09 511593001 5/1112020 Co-60 -1.32E+OO 4.51E+OO 1.43E+Ol u MU 09 511593001 5/1112020 Cr-51 -9.22E+OO 2.72E+Ol 8.45E+Ol u MU 09 511593001 5/1112020 Cs-134 3.46E+OO 3.12E+OO 1.llE+Ol u MU 09 511593001 5/1112020 Cs-137 -9.14E+OO 5.40E+OO 1.16E+Ol u MU 09 511593001 5/1112020 Fe-59 7.43E+OO 8.91E+OO 3.16E+Ol u MU 09 511593001 5/11/2020 I-131 -5.22E+OO 6.98E+OO 2.04E+Ol u MU 09 511593001 5/1112020 K-40 1.42E+03 1.36E+02 1.17E+02 MU 09 511593001 5/1112020 La-140 -5.92E+OO 8.82E+OO 2.53E+Ol u MU 09 511593001 5/11/2020 Mn-54 2.56E+OO 3.53E+OO 1.20E+Ol u MU 09 511593001 5/1112020 Nb-95 3.45E+OO 4.87E+OO 9.32E+OO u MU 09 511593001 5/1112020 Pb-212 8.73£-01 5.20E+OO 1.45E+Ol u MU 09 511593001 5/1112020 Pb-214 -7.82£-02 8.51E+OO 2.48E+Ol u MU 09 511593001 5/1112020 Ra-226 8.llE+OO 8.78E+OO 2.82E+Ol u MU 09 511593001 511112020 Ru-103 -1.41E+OO 2.97E+OO 9.63E+OO u MU 09 511593001 5/1112020 Ru-106 1.09E+Ol 2.96E+Ol 9.13E+Ol u MU 09 511593001 5/11/2020 Sb-124 1.30E+OO 1.02E+Ol 3.32E+Ol u MU 09 511593001 5/1112020 Sb-125 7.70E+OO 7.57E+OO 2.68E+Ol u MU 09 511593001 511112020 Se-75 -3.04£-01 3.05E+OO 9.85E+OO u MU 09 511593001 5/11/2020 Th-228 8.73£-01 5.20E+OO 1.45E+Ol u MU 09 511593001 5/11/2020 Th-230 8.1 lE+OO 8.78E+OO 2.82E+Ol u MU 09 511593001 5/11/2020 Tl-208 6.70E+OO 3.69E+OO 1.27E+Ol u MU 09 511593001 5/11/2020 Zn-65 1.57E+Ol 8.43E+OO 3.04E+Ol u MU 09 511593001 5/11/2020 Zr-95 8.05E+OO 6.08E+OO 2.14E+Ol u 194

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/kg) (pCi/kg) (pCi/kg)

MU 09 528380001 11/18/2020 Ac-228 9.87E+OO l.50E+Ol 2.93E+Ol u MU 09 528380001 11/18/2020 Ag-108m -4.16E-Ol 1.27E+OO 4.18E+OO u MU 09 528380001 11/18/2020 Ag-llOm -2.32E-Ol 2.09E+OO 7.06E+OO u MU 09 528380001 11/18/2020 Ba-140 6.06E+OO 1.06E+Ol 3.57E+Ol u MU 09 528380001 11/18/2020 Be-7 3.99E+Ol 2.90E+Ol 4.96E+Ol u MU 09 528380001 11/18/2020 Bi-214 O.OOE+OO 6.40E+OO 8.96E+OO u MU 09 528380001 11/18/2020 Ce-141 -5.79E+OO 3.04E+OO 8.21E+OO u MU 09 528380001 11/18/2020 Ce-144 8.68E+OO 8.50E+OO 2.79E+Ol u MU 09 528380001 11/18/2020 Co-57 -5.02E-Ol l.05E+OO 3.36E+OO u MU 09 528380001 11/18/2020 Co-58 -3.22E+OO 1.72E+OO 4.04E+OO u MU 09 528380001 11/18/2020 Co-60 9.36E-Ol 1.60E+OO 5.47E+OO u MU 09 528380001 11/18/2020 Cr-51 l.65E+OO l.38E+Ol 4.75E+Ol u MU 09 528380001 11/18/2020 Cs-134 -4.74E-Ol 1.87E+OO 5.86E+OO u MU 09 528380001 11/18/2020 Cs-137 -2.51E+OO 2.32E+OO 6.40E+OO u MU 09 528380001 11/18/2020 Fe-59 -5.44E+OO 3.93E+OO 1.1 IE+Ol u MU 09 528380001 11/18/2020 1-131 -2.35E+OO 5.98E+OO 1.69E+Ol u MU 09 528380001 11/18/2020 K-40 l.58E+03 1.05E+02 4.64E+Ol MU 09 528380001 11/18/2020 La-140 8.56E+OO 6.49E+OO 1.47E+Ol u MU 09 528380001 11/18/2020 Mn-54 -8.95E-Ol 1.73E+OO 5.27E+OO u MU 09 528380001 11/18/2020 Nb-95 3.93E+OO 1.90E+OO 6.14E+OO u MU 09 528380001 11/18/2020 Pb-212 2.llE+Ol 4.33E+OO 8.26E+OO MU 09 528380001 11/18/2020 Pb-214 2.0IE+Ol 6.96E+OO 9.48E+OO MU 09 528380001 11/18/2020 Ra-226 O.OOE+OO 6.40E+OO 8.96E+OO u MU 09 528380001 11/18/2020 Ru-103 4.09E-Ol 1.71E+OO 5.72E+OO u MU 09 528380001 11/18/2020 Ru-106 8.80E+OO l.33E+Ol 4.46E+Ol u MU 09 528380001 11/18/2020 Sb-124 1.05E+OO 3.49E+OO 1.16E+Ol u MU 09 528380001 11/18/2020 Sb-125 -7.31E+OO 4.23E+OO 1.18E+Ol u MU 09 528380001 11/18/2020 Se-75 -4.50E-Ol 2.llE+OO 6.52E+OO u MU 09 528380001 11/18/2020 Th-228 2.llE+Ol 4.33E+OO 8.26E+OO MU 09 528380001 11/18/2020 Th-230 O.OOE+OO 6.40E+OO 8.96E+OO u MU 09 528380001 11/18/2020 Tl-208 3.77E+OO 3.02E+OO 4.72E+OO u MU 09 528380001 11/18/2020 Zn-65 2.62E+OO 3.55E+OO 1.22E+Ol u MU 09 528380001 11/18/2020 Zr-95 -l.41E-Ol 3.36E+OO 1.07E+Ol u MU 56 511611002 5/14/2020 Ac-228 -5.84E+OO 9.05E+OO 2.73E+Ol u MU 56 511611002 5/14/2020 Ag-108m l.54E+OO 1.46E+OO 4.99E+OO u MU 56 511611002 5/14/2020 Ag-llOm -4.12E+OO 2.78E+OO 7.33E+OO u MU 56 511611002 5/14/2020 Ba-140 l.09E+Ol 1.14E+Ol 3.86E+Ol u MU 56 511611002 5/14/2020 Be-7 8.28E+Ol 2.90E+Ol 4.63E+Ol MU 56 511611002 5/14/2020 Bi-214 7.56E+OO 6.35E+OO l.50E+Ol u MU 56 511611002 511412020 Ce-141 -8.20E+OO 3.93E+OO 8.77E+OO u MU 56 511611002 5/14/2020 Ce-144 -3.39E+OO 9.00E+OO 2.89E+Ol u MU 56 511611002 5/14/2020 Co-57 -1.07E-Ol 1.16E+OO 3.79E+OO u MU 56 511611002 5/14/2020 Co-58 3.32E+OO 2.21E+OO 7.30E+OO u MU 56 511611002 5/14/2020 Co-60 l.90E+OO 2.46E+OO 7.55E+OO u MU 56 511611002 5/14/2020 Cr-51 8.56E+OO I.77E+Ol 6.llE+Ol u MU 56 511611002 5/14/2020 Cs-134 3.96E+OO 2.0IE+OO 6.65E+OO u MU 56 511611002 5/14/2020 Cs-137 -8.07E-Ol 2.25E+OO 6.58E+OO u MU 56 511611002 5/14/2020 Fe-59 -1.87E-Ol 4.04E+OO l.34E+Ol u MU 56 511611002 5/14/2020 1-131 9.34E+OO 4.93E+OO 1.64E+Ol u MU 56 511611002 5/14/2020 K-40 l.41E+03 1.10E+02 5.80E+Ol 195

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/kg) (pCi/kg) (pCi/kg)

MU 56 511611002 5/14/2020 La-140 -6.06E+OO 5.09E+OO l.36E+Ol u MU 56 511611002 5/14/2020 Mn-54 l.35E+OO l.65E+OO 5.81E+OO u MU 56 511611002 5/14/2020 Nb-95 2.47E+OO 2.04E+OO 6.79E+OO u MU 56 511611002 5/14/2020 Pb-212 3.IOE+OO 4.87E+OO l.19E+Ol u MU 56 511611002 5/14/2020 Pb-214 l.07E+Ol 8.02E+OO 1.41E+Ol u MU 56 511611002 5/14/2020 Ra-226 7.56E+OO 6.35E+OO l.50E+Ol u MU 56 511611002 5/14/2020 Ru-103 3.30E+OO 2.52E+OO 6.76E+OO u MU 56 511611002 5/14/2020 Ru-106 -7.82E+OO l.56E+Ol 4.86E+Ol u MU 56 511611002 5/14/2020 Sb-124 -l.05E+OO 4.00E+OO l.30E+Ol u MU 56 511611002 5/14/2020 Sb-125 -2.0IE+OO 4.18E+OO l.35E+Ol u MU 56 511611002 5/14/2020 Se-75 8.30E-Ol l.99E+OO 6.32E+OO u MU 56 511611002 5/14/2020 Th-228 3.IOE+OO 4.87E+OO l.19E+Ol u MU 56 511611002 5/14/2020 Th-230 7.56E+OO 6.35E+OO 1.50E+Ol u MU 56 511611002 5/14/2020 Tl-208 4.57E+OO 3.75E+OO 6.47E+OO u MU 56 511611002 5/14/2020 Zn-65 l.96E+OO 4.26E+OO 1.45E+Ol u MU 56 511611002 5/14/2020 Zr-95 -5.30E+OO 3.96E+OO l.08E+Ol u MU 56 529883002 12/9/2020 Ac-228 3.60E+Ol 2.13E+Ol 4.44E+Ol u MU 56 529883002 12/9/2020 Ag-108m l.20E+OO l.78E+OO 6.23E+OO u MU 56 529883002 12/9/2020 Ag-llOm -1.0IE+OO 3.98E+OO l.05E+Ol u MU 56 529883002 12/9/2020 Ba-140 2.34E+Ol l.21E+Ol 4.llE+Ol u MU 56 529883002 12/9/2020 Be-7 3.75E+Ol 3.IOE+Ol 5.58E+Ol u MU 56 529883002 12/9/2020 Bi-214 -7.16E-Ol 6.92E+OO 2.15E+Ol u MU 56 529883002 12/9/2020 Ce-141 7.27E+OO 4.99E+OO l.12E+Ol u MU 56 529883002 12/9/2020 Ce-144 -l.78E+OO 1.27E+Ol 4.19E+Ol u MU 56 529883002 12/9/2020 Co-57 2.03E+OO l.69E+OO 5.62E+OO u MU 56 529883002 12/9/2020 Co-58 -2.94E+OO 2.69E+OO 7.59E+OO u MU 56 529883002 12/9/2020 Co-60 3.37E+OO 2.97E+OO l.06E+Ol u MU 56 529883002 12/9/2020 Cr-51 l.09E+Ol 2.14E+Ol 6.87E+Ol u MU 56 529883002 12/9/2020 Cs-134 7.38E+OO 3.15E+OO 1.05E+Ol u MU 56 529883002 12/9/2020 Cs-137 -2.75E+OO 3.06E+OO 7.98E+OO u MU 56 529883002 12/9/2020 Fe-59 -2.29E+OO 5.65E+OO l.60E+Ol u MU 56 529883002 12/9/2020 I-131 -5.04E+OO 4.0IE+OO 1.08E+Ol u MU 56 529883002 12/9/2020 K-40 l.28E+03 l.20E+02 8.05E+Ol MU 56 529883002 12/9/2020 La-140 -6.50E+OO 4.61E+OO l.13E+Ol u MU 56 529883002 12/9/2020 Mn-54 6.77E-Ol 2.68E+OO 8.83E+OO u MU 56 529883002 12/9/2020 Nb-95 -3.02E+OO 2.81E+OO 8.IOE+OO u MU 56 529883002 12/9/2020 Pb-212 9.29E-Ol 7.llE+OO 1.54E+Ol u MU 56 529883002 12/9/2020 Pb-214 l.28E+Ol 9.82E+OO 2.26E+Ol u MU 56 529883002 12/9/2020 Ra-226 -7.16E-Ol 6.92E+OO 2.15E+Ol u MU 56 529883002 12/9/2020 Ru-103 -3.19E+OO 3.06E+OO 7.20E+OO u MU 56 529883002 12/9/2020 Ru-106 8.39E+OO l.75E+Ol 6.00E+Ol u MU 56 529883002 12/9/2020 Sb-124 5.12E+OO 5.81E+OO 2.IOE+Ol u MU 56 529883002 12/9/2020 Sb-125 2.69E+OO 5.65E+OO 1.96E+Ol u MU 56 529883002 12/9/2020 Se-75 3.06E+OO 2.65E+OO 8.64E+OO u MU 56 529883002 12/9/2020 Th-228 9.29E-Ol 7.llE+OO 1.54E+Ol u MU 56 529883002 12/9/2020 Th-230 -7.16E-01 6.92E+OO 2.15E+Ol u MU 56 529883002 12/9/2020 Tl-208 -l.19E+OO 3.llE+OO 9.54E+OO u MU 56 529883002 12/9/2020 Zn-65 -3.09E+OO 6.44E+OO 1.81E+Ol u MU 56 529883002 12/9/2020 Zr-95 -1.23E+OO 4.IOE+OO 1.14E+Ol u 196

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/kg) (pCi/kg) (pCi/kg)

MU 59 511593002 5/18/2020 Ac-228 -3.92E+Ol 2.94E+Ol 7.94E+Ol u MU 59 511593002 5/18/2020 Ag-108m -2.18E-01 5.00E+OO l.53E+Ol u MU 59 511593002 5/18/2020 Ag-llOm -2.23E+OO 7.58E+OO 2.37E+Ol u MU 59 511593002 5/18/2020 Ba-140 -5.62E+OO 2.09E+Ol 6.85E+Ol u MU 59 511593002 5/18/2020 Be-7 3.23E+02 l.44E+02 1.21E+02 MU 59 511593002 5/18/2020 Bi-214 2.44E+Ol 2.60E+Ol 4.40E+Ol u MU 59 511593002 5/18/2020 Ce-141 -4.65E+OO 6.66E+OO 2.12E+Ol u MU 59 511593002 5/18/2020 Ce-144 -1.26E+Ol 2.44E+Ol 7.90E+Ol u MU 59 511593002 5/18/2020 Co-57 2.95E+OO 3.20E+OO 1.08E+Ol u MU 59 511593002 5/18/2020 Co-58 1.07E+OO 4.86E+OO 1.60E+Ol u MU 59 511593002 5/18/2020 Co-60 1.05E+Ol 6.54E+OO 2.29E+Ol u MU 59 511593002 5/18/2020 Cr-51 -3.99E+Ol 4.30E+Ol 1.25E+02 u MU 59 511593002 5/18/2020 Cs-134 1.02E+Ol 6.lOE+OO 2.06E+Ol u MU 59 511593002 5/18/2020 Cs-137 6.76E+OO 5.77E+OO 1.96E+Ol u MU 59 511593002 5/18/2020 Fe-59 -2.09E+OO 1.00E+Ol 3.33E+Ol u MU 59 511593002 5/18/2020 1-131 6.39E+OO 6.05E+OO 2.llE+Ol u MU 59 511593002 5/18/2020 K-40 l.54E+03 1.73E+02 1.11E+02 MU 59 511593002 5/18/2020 La-140 -9.71E+OO 7.88E+OO 2.lOE+Ol u MU 59 511593002 5/18/2020 Mn-54 5.92E-01 6.41E+OO 2.08E+Ol u MU 59 511593002 5/18/2020 Nb-95 -1.08E-01 5.23E+OO 1.70E+Ol u MU 59 511593002 5/18/2020 Pb-212 8.19E+OO 1.46E+Ol 2.39E+Ol u MU 59 511593002 5/18/2020 Pb-214 -8.20E+OO 1.70E+Ol 4.12E+Ol u MU 59 511593002 5/18/2020 Ra-226 2.44E+Ol 2.60E+Ol 4.40E+Ol u MU 59 511593002 5/18/2020 Ru-103 -4.50E+OO 4.50E+OO 1.38E+Ol u MU 59 511593002 5/18/2020 Ru-106 2.38E+Ol 4.38E+Ol l.49E+02 u MU 59 511593002 5/18/2020 Sb-124 1.09E+Ol 1.18E+Ol 4.17E+Ol u MU 59 511593002 5/18/2020 Sb-125 -1.08E+Ol 1.25E+Ol 3.98E+Ol u MU 59 511593002 5/18/2020 Se-75 -1.12E+Ol 6.48E+OO 1.71E+Ol u MU 59 511593002 5/18/2020 Th-228 8.19E+OO 1.46E+Ol 2.39E+Ol u MU 59 511593002 5/18/2020 Th-230 2.44E+Ol 2.60E+Ol 4.40E+Ol u MU 59 511593002 5/18/2020 Tl-208 -9.26E+OO 8.39E+OO 2.24E+Ol u MU 59 511593002 5/18/2020 Zn-65 -8.96E+OO l.20E+Ol 3.78E+Ol u MU 59 511593002 5/18/2020 Zr-95 -6.13E+OO 9.18E+OO 2.80E+Ol u MU 59 528380002 11118/2020 Ac-228 -9.66E+OO 8.86E+OO 2.51E+Ol u MU 59 528380002 11118/2020 Ag-108m 3.33E-01 1.32E+OO 4.48E+OO u MU 59 528380002 11/18/2020 Ag-llOm 9.52E-02 2.08E+OO 6.77E+OO u MU 59 528380002 11/18/2020 Ba-140 9.55E+OO 1.14E+Ol 3.89E+Ol u MU 59 528380002 11/18/2020 Be-7 6.97E+Ol 2.35E+Ol 5.14E+Ol MU 59 528380002 11118/2020 Bi-214 O.OOE+OO 6.76E+OO 1.43E+Ol u MU 59 528380002 11/18/2020 Ce-141 2.26E+OO 3.04E+OO 9.12E+OO u MU 59 528380002 11/18/2020 Ce-144 -5.1 IE+OO 9.60E+OO 3.0lE+Ol u MU 59 528380002 11118/2020 Co-57 6.17E-01 1.28E+OO 4.17E+OO u MU 59 528380002 11118/2020 Co-58 7.92E-01 1.68E+OO 5.60E+OO u MU 59 528380002 11/18/2020 Co-60 -8.88E-01 1.41E+OO 4.47E+OO u MU 59 528380002 11118/2020 Cr-51 -5.69E+OO l.60E+Ol 5.38E+Ol u MU 59 528380002 11/18/2020 Cs-134 -1.76E+OO l.62E+OO 4.70E+OO u MU 59 528380002 11118/2020 Cs-137 4.60E-01 1.66E+OO 4.99E+OO u MU 59 528380002 11118/2020 Fe-59 -2.73E+OO 3.88E+OO l.16E+Ol u MU 59 528380002 11118/2020 1-131 l.55E+OO 4.88E+OO 1.68E+Ol u MU 59 528380002 11118/2020 K-40 l.13E+03 8.87E+Ol 4.65E+Ol 197

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/kg) (pCi/kg) (pCi/kg)

MU 59 528380002 11/18/2020 La-140 -9.59E+OO 4.23E+OO 8.47E+OO u MU 59 528380002 11/18/2020 Mn-54 -1.08E+OO l.39E+OO 4.18E+OO u MU 59 528380002 11/18/2020 Nb-95 -2.12E+OO 2.IOE+OO 5.42E+OO u MU 59 528380002 11/18/2020 Pb-212 O.OOE+OO 5.93E+OO l.08E+Ol u MU 59 528380002 11/18/2020 Pb-214 5.36E+OO 5.92E+OO l.27E+Ol u MU 59 528380002 11/18/2020 Ra-226 O.OOE+OO 6.76E+OO 1.43E+Ol u MU 59 528380002 11/18/2020 Ru-103 5.91E-02 l.67E+OO 5.62E+OO u MU 59 528380002 11/18/2020 Ru-106 l.56E-Ol l.19E+Ol 3.95E+Ol u MU 59 528380002 11/18/2020 Sb-124 4.91E+OO 3.66E+OO l.32E+Ol u MU 59 528380002 11/18/2020 Sb-125 -5.09E-Ol 4.00E+OO l.34E+Ol u MU 59 528380002 11/18/2020 Se-75 5.73E+OO 2.61E+OO 6.90E+OO u MU 59 528380002 11/18/2020 Th-228 O.OOE+OO 5.93E+OO l.08E+Ol u MU 59 528380002 11/18/2020 Th-230 O.OOE+OO 6.76E+OO l.43E+Ol u MU 59 528380002 11/18/2020 Tl-208 3.20E-Ol 2.95E+OO 3.82E+OO u MU 59 528380002 11/18/2020 Zn-65 -4.22E+OO 3.90E+OO l.IIE+Ol u MU 59 528380002 11/18/2020 Zr-95 4.68E+OO 2.98E+OO l.OOE+Ol u MS 06 511611004 5/14/2020 Sr-89 -1.12E+02 3.30E+Ol 8.76E+Ol u MS 06 511611004 5/14/2020 Sr-90 -1.29E+02 3.88E+Ol l.53E+02 u MS 06 529883004 12/9/2020 Sr-89 -1.17E+Ol 5.46E+Ol J.30E+02 u MS 06 529883004 12/9/2020 Sr-90 -3.80E+Ol 3.95E+Ol l.40E+02 u MS 56 511611005 5/14/2020 Sr-89 7.63E+OO 2.81E+Ol 6.94E+Ol u MS 56 511611005 5/14/2020 Sr-90 -1.33E+Ol l.85E+Ol 6.47E+Ol u MS 56 529883005 12/9/2020 Sr-89 -1.12E+02 3.53E+Ol 9.00E+Ol u MS 56 529883005 12/9/2020 Sr-90 6.71E+Ol 3.80E+Ol l.03E+02 u 198

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/kg) (pCi/kg) (pCi/kg)

SE 02 511608001 5/14/2020 Ac-228 l.69E+03 l.31E+02 9.68E+Ol SE 02 511608001 5/14/2020 Ag-108m 6.0IE+OO 6.40E+OO 2.18E+Ol u SE 02 511608001 5/14/2020 Ag-llOm -l.18E+OO l.14E+Ol 3.32E+Ol u SE 02 511608001 5/14/2020 Ba-140 5.68E+Ol 4.48E+Ol l.33E+02 u SE 02 511608001 5/14/2020 Be-7 -6.64E+Ol 6.49E+Ol 2.06E+02 u SE 02 511608001 5/14/2020 Bi-214 l.09E+03 6.52E+Ol 5.15E+Ol SE 02 511608001 5/14/2020 Ce-141 -7.92E+OO l.35E+Ol 4.59E+Ol u SE 02 511608001 5/14/2020 Ce-144 -l.08E+02 5.44E+Ol l.61E+02 u SE 02 511608001 5/14/2020 Co-57 -l.05E+Ol 7.05E+OO 2.13E+Ol u SE 02 511608001 5/14/2020 Co-58 -1.09E+Ol 7.90E+OO 2.41E+Ol u SE 02 511608001 5/14/2020 Co-60 -l.56E+OO 7.53E+OO 2.50E+Ol u SE 02 511608001 5/14/2020 Cr-51 -2.87E+Ol 6.77E+Ol 2.36E+02 u SE 02 511608001 5/14/2020 Cs-134 O.OOE+OO 2.33E+Ol 3.78E+Ol u SE 02 511608001 5/14/2020 Cs-137 5.58E+OO 7.90E+OO 2.76E+Ol u SE 02 511608001 5/14/2020 Fe-59 -2.14E+Ol l.62E+Ol 5.03E+Ol u SE 02 511608001 5/14/2020 1-131 l.52E+Ol l.33E+Ol 4.60E+Ol u SE 02 511608001 5/14/2020 K-40 l.49E+04 9.86E+02 2.40E+02 SE 02 511608001 5/14/2020 La-140 -1.79E+Ol l.38E+Ol 3.99E+Ol u SE 02 511608001 5/14/2020 Mn-54 2.64E+Ol l.24E+Ol 2.55E+Ol UI SE 02 511608001 5/14/2020 Nb-95 2.93E+Ol l.40E+Ol 3.08E+Ol u SE 02 511608001 5/14/2020 Pb-212 l.86E+03 9.60E+Ol 4.40E+Ol SE 02 511608001 5/14/2020 Pb-214 l.37E+03 7.81E+Ol 5.46E+Ol SE 02 511608001 5/14/2020 Ra-226 l.09E+03 6.52E+Ol 5.15E+Ol SE 02 511608001 5/14/2020 Ru-103 -l.37E+Ol 9.18E+OO 2.40E+Ol u SE 02 511608001 5/14/2020 Ru-106 -5.73E+Ol 6.54E+Ol 2.19E+02 u SE 02 511608001 5/14/2020 Sb-124 4.77E+OO l.78E+Ol 5.12E+Ol u SE 02 511608001 5/14/2020 Sb-125 l.14E+Ol l.99E+Ol 6.82E+Ol u SE 02 511608001 5/14/2020 Se-75 -l.20E+Ol 1.02E+Ol 3.29E+Ol u SE 02 511608001 5/14/2020 Th-228 l.86E+03 9.60E+Ol 4.40E+Ol SE 02 511608001 5/14/2020 Th-230 l.09E+03 6.52E+Ol 5.15E+Ol SE 02 511608001 5/14/2020 Tl-208 5.05E+02 3.02E+Ol 2.60E+Ol SE 02 511608001 5/14/2020 Zn-65 -2.03E+Ol 2.llE+Ol 5.86E+Ol u SE 02 511608001 5/14/2020 Zr-95 3.1 IE+Ol l.80E+Ol 5.32E+Ol u SE 02 529874001 12/9/2020 Ac-228 l.33E+03 2.03E+02 2.32E+02 SE 02 529874001 12/9/2020 Ag-108m 7.67E+OO l.55E+Ol 5.55E+Ol u SE 02 529874001 12/9/2020 Ag-llOm -2.04E+Ol 3.03E+Ol 9.22E+Ol u SE 02 529874001 12/9/2020 Ba-140 -1.60E+02 2.39E+02 7.82E+02 u SE 02 529874001 12/9/2020 Be-7 -l.44E+02 2.00E+02 5.89E+02 u SE 02 529874001 12/9/2020 Bi-214 9.88E+02 l.21E+02 9.49E+Ol SE 02 529874001 12/9/2020 Ce-141 -5.llE+Ol 3.84E+Ol l.l 1E+02 u SE 02 529874001 12/9/2020 Ce-144 -7.38E+Ol 9.22E+Ol 3.11E+02 u SE 02 529874001 12/9/2020 Co-57 1.62E+OO l.IOE+Ol 3.93E+Ol u SE 02 529874001 12/9/2020 Co-58 -4.22E+Ol 2.72E+Ol 7.27E+Ol u SE 02 529874001 12/9/2020 Co-60 3.96E+Ol 2.40E+Ol 8.53E+Ol u SE 02 529874001 12/9/2020 Cr-51 -4.35E+OO 2.42E+02 7.90E+02 u SE 02 529874001 12/9/2020 Cs-134 4.94E+Ol 2.91E+Ol 9.80E+Ol u SE 02 529874001 12/9/2020 Cs-137 8.63E+OO 2.06E+Ol 6.43E+Ol u SE 02 529874001 12/9/2020 Fe-59 -5.61E+Ol 5.07E+Ol l.51E+02 u SE 02 529874001 12/9/2020 1-131 -l.69E+02 l.23E+02 3.87E+02 u SE 02 529874001 12/9/2020 K-40 l.42E+04 l.05E+03 5.83E+02 199

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/kg) (pCi/kg) (pCi/kg)

SE 02 529874001 12/9/2020 La-140 -3.46E+01 8.08E+01 2.50E+02 u SE 02 529874001 12/9/2020 Mn-54 -l.29E+01 2.26E+Ol 7.05E+01 u SE 02 529874001 12/9/2020 Nb-95 3.76E+01 2.81E+01 8.94E+Ol u SE 02 529874001 12/9/2020 Pb-212 1.38E+03 9.61E+Ol 9.06E+01 SE 02 529874001 12/9/2020 Pb-214 1.18E+03 1.llE+02 3.21E+02 SE 02 529874001 12/9/2020 Ra-226 9.88E+02 l.21E+02 9.49E+01 SE 02 529874001 12/9/2020 Ru-103 -3.51E+OO 2.17E+01 6.66E+Ol u SE 02 529874001 12/9/2020 Ru-106 -l.67E+01 l.74E+02 5.86E+02 u SE 02 529874001 12/9/2020 Sb-124 -4.63E+01 5.23E+01 l.51E+02 u SE 02 529874001 12/9/2020 Sb-125 -3.14E+Ol 4.43E+01 l.48E+02 u SE 02 529874001 12/9/2020 Se-75 l.06E+01 2.52E+01 7.88E+01 u SE 02 529874001 12/9/2020 Th-228 1.38E+03 9.61E+Ol 9.06E+01 SE 02 529874001 12/9/2020 Th-230 9.88E+02 l.21E+02 9.49E+01 SE 02 529874001 12/9/2020 Tl-208 5.24E+02 6.16E+01 6.IOE+01 SE 02 529874001 12/9/2020 Zn-65 -9.13E+01 5.42E+01 1.17E+02 u SE 02 529874001 12/9/2020 Zr-95 8.62E+01 4.84E+01 l.66E+02 u SE 07 511615001 5/11/2020 Ac-228 3.06E+02 6.40E+01 8.72E+01 SE 07 511615001 5/11/2020 Ag-108m -3.47E+OO 5.38E+OO l.82E+Ol u SE 07 511615001 5/11/2020 Ag-1 lOm -l.34E+01 l.09E+Ol 3.15E+01 u SE 07 511615001 5/11/2020 Ba-140 -2.62E+01 3.74E+01 l.22E+02 u SE 07 511615001 5/11/2020 Be-7 -l.72E+01 5.17E+01 l.77E+02 u SE 07 511615001 5/11/2020 Bi-214 2.79E+02 3.64E+01 4.46E+01 SE 07 511615001 5/11/2020 Ce-141 -8.90E+OO l.IOE+01 3.36E+01 u SE 07 511615001 5/11/2020 Ce-144 3.79E+OO 3.41E+01 l.20E+02 u SE 07 511615001 5/11/2020 Co-57 2.82E-01 4.30E+OO l.52E+01 u SE 07 511615001 5/11/2020 Co-58 -8.59E+OO 7.17E+OO 2.09E+01 u SE 07 511615001 5/11/2020 Co-60 4.91E+OO 8.0IE+OO 2.76E+01 u SE 07 511615001 5/11/2020 Cr-51 6.60E+01 5.75E+01 2.07E+02 u SE 07 511615001 5/11/2020 Cs-134 6.89E+OO 8.55E+OO 2.88E+01 u SE 07 511615001 5/11/2020 Cs-137 -2.61E+OO 6.89E+OO 2.27E+01 u SE 07 511615001 5/11/2020 Fe-59 1.32E+Ol l.75E+01 6.13E+Ol u SE 07 511615001 5/11/2020 I-131 -3.51E+OO l.48E+01 5.21E+01 u SE 07 511615001 5/11/2020 K-40 l.72E+04 l.06E+03 2.31E+02 SE 07 511615001 5/11/2020 La-140 l.60E+OO 1.38E+01 4.59E+01 u SE 07 511615001 5/11/2020 Mn-54 -l.61E+OO 6.91E+OO 2.12E+01 u SE 07 511615001 5/11/2020 Nb-95 -l.44E+01 9.07E+OO 2.43E+01 u SE 07 511615001 5/11/2020 Pb-212 3.60E+02 3.21E+01 3.85E+01 SE 07 511615001 5/11/2020 Pb-214 3.26E+02 3.52E+01 4.57E+01 SE 07 511615001 5/11/2020 Ra-226 2.79E+02 3.64E+01 4.46E+01 SE 07 511615001 5/11/2020 Ru-103 6.32E+OO 6.56E+OO 2.31E+01 u SE 07 511615001 5/11/2020 Ru-106 -5.48E+Ol 6.03E+01 l.91E+02 u SE 07 511615001 5/11/2020 Sb-124 7.58E+OO l.22E+01 4.25E+01 u SE 07 511615001 5/11/2020 Sb-125 3.47E+OO l.68E+01 5.92E+01 u SE 07 511615001 5/11/2020 Se-75 7.73E+OO 9.23E+OO 2.85E+01 u SE 07 511615001 5/11/2020 Th-228 3.60E+02 3.21E+Ol 3.85E+01 SE 07 511615001 5/11/2020 Th-230 2.79E+02 3.64E+01 4.46E+01 SE 07 511615001 5/11/2020 Tl-208 8.37E+01 I.77E+01 2.36E+Ol SE 07 511615001 5/11/2020 Zn-65 l.64E+01 2.05E+01 6.39E+01 u SE 07 511615001 5/11/2020 Zr-95 4.17E+Ol 4.17E+Ol 4.61E+01 u 200

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/kg) (pCi/kg) (pCi/kg)

SE 07 528391001 11119/2020 Ac-228 O.OOE+OO 1.25E+02 2.97E+02 u SE 07 528391001 11/19/2020 Ag-108m 1.95E+Ol 1.02E+Ol 3.42E+Ol u SE 07 528391001 11/19/2020 Ag-llOm 1.18E+Ol 2.00E+Ol 6.86E+Ol u SE 07 528391001 11/19/2020 Ba-140 3.94E+02 3.78E+02 7.24E+02 u SE 07 528391001 11119/2020 Be-7 l.33E+02 l.37E+02 4.65E+02 u SE 07 528391001 11/19/2020 Bi-214 2.87E+02 5.06E+Ol 8.89E+Ol SE 07 528391001 11119/2020 Ce-141 5.04E+Ol 5.76E+Ol 8.92E+Ol u SE 07 528391001 11/19/2020 Ce-144 1.20E+02 7.43E+Ol 2.53E+02 u SE 07 528391001 11/19/2020 Co-57 -4.l IE+OO 7.65E+OO 2.73E+Ol u SE 07 528391001 11/19/2020 Co-58 9.12E-01 l.45E+Ol 4.89E+Ol u SE 07 528391001 11/19/2020 Co-60 -1.87E+Ol 1.59E+Ol 4.62E+Ol u SE 07 528391001 11/19/2020 Cr-51 -7.46E+Ol 1.86E+02 6.17E+02 u SE 07 528391001 11119/2020 Cs-134 6.33E+OO 1.47E+Ol 5.08E+Ol u SE 07 528391001 11/19/2020 Cs-137 -5.64E+OO 1.20E+Ol 3.98E+Ol u SE 07 528391001 11/19/2020 Fe-59 3.77E+Ol 4.99E+Ol 1.69E+02 u SE 07 528391001 11119/2020 1-131 -9.56E+Ol 1.71E+02 5.54E+02 u SE 07 528391001 11119/2020 K-40 l.96E+04 1.26E+03 4.31E+02 SE 07 528391001 11119/2020 La-140 -3.39E+Ol 6.1 IE+Ol 1.84E+02 u SE 07 528391001 11119/2020 Mn-54 9.88E+OO l.38E+Ol 4.77E+Ol u SE 07 528391001 11119/2020 Nb-95 -1.86E+OO 1.76E+Ol 5.90E+Ol u SE 07 528391001 11119/2020 Pb-212 3.89E+02 4.43E+Ol 6.50E+Ol SE 07 528391001 11119/2020 Pb-214 2.66E+02 6.05E+Ol 8.18E+OI SE 07 528391001 11/19/2020 Ra-226 2.87E+02 5.06E+Ol 8.89E+Ol SE 07 528391001 11119/2020 Ru-103 -3.40E+Ol 2.03E+Ol 5.35E+Ol u SE 07 528391001 11/19/2020 Ru-106 3.34E+Ol 1.06E+02 3.71E+02 u SE 07 528391001 11119/2020 Sb-124 -l.81E+Ol 2.68E+Ol 7.61E+Ol u SE 07 528391001 11119/2020 Sb-125 2.08E+Ol 2.92E+Ol 1.00E+02 u SE 07 528391001 11119/2020 Se-75 2.23E+Ol 1.61E+Ol 5.63E+Ol u SE 07 528391001 11119/2020 Th-228 3.89E+02 4.43E+Ol 6.50E+Ol SE 07 528391001 11119/2020 Th-230 2.87E+02 5.06E+Ol 8.89E+Ol SE 07 528391001 11119/2020 Tl-208 8.14E+Ol 2.54E+Ol 3.63E+Ol SE 07 528391001 11119/2020 Zn-65 -2.14E+Ol 4.29E+Ol l.35E+02 u SE 07 528391001 11119/2020 Zr-95 2.31E+Ol 3.IOE+Ol l.08E+02 u SE 08 511615002 5/11/2020 Ac-228 4.94E+02 7.47E+Ol 8.69E+Ol SE 08 511615002 5/1112020 Ag-108m -2.22E+OO 4.76E+OO 1.64E+Ol u SE 08 511615002 5/11/2020 Ag-1 lOm -4.79E+OO 9.98E+OO 3.llE+Ol u SE 08 511615002 5/11/2020 Ba-140 -4.29E+Ol 3.62E+Ol 1.13E+02 u SE 08 511615002 5/1112020 Be-7 5.89E+Ol 5.65E+Ol 1.99E+02 u SE 08 511615002 5/11/2020 Bi-214 3.04E+02 3.43E+Ol 4.62E+Ol SE 08 511615002 5/11/2020 Ce-141 -2.24E+Ol 1.17E+Ol 3.24E+Ol u SE 08 511615002 5/11/2020 Ce-144 -3.14E+OO 3.24E+Ol 1.13E+02 u SE 08 511615002 5/1112020 Co-57 5.07E+OO 4.33E+OO 1.51E+Ol u SE 08 511615002 5/1112020 Co-58 7.52E+OO 7.78E+OO 2.41E+Ol u SE 08 511615002 5/1112020 Co-60 4.58E+OO 7.86E+OO 2.73E+Ol u SE 08 511615002 5/11/2020 Cr-51 9.9IE-01 5.80E+Ol 2.09E+02 u SE 08 511615002 5/1112020 Cs-134 O.OOE+OO 2.29E+Ol 3.14E+Ol u SE 08 511615002 5/1112020 Cs-137 -4.34E+OO 7.1 IE+OO 2.20E+Ol u SE 08 511615002 5/11/2020 Fe-59 O.OOE+OO 6.89E+Ol 6.15E+Ol u SE 08 511615002 5/11/2020 1-131 -2.66E+Ol 1.51E+Ol 4.57E+Ol u SE 08 511615002 5/1112020 K-40 2.36E+04 1.21E+03 1.75E+02 201

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/kg) (pCi/kg) (pCi/kg)

SE 08 511615002 5/11/2020 La-140 2.31E+OO l.08E+Ol 3.26E+Ol u SE 08 511615002 5/11/2020 Mn-54 O.OOE+OO 1.14E+Ol l.80E+Ol u SE 08 511615002 5/11/2020 Nb-95 -7.49E+OO 9.28E+OO 2.73E+Ol u SE 08 511615002 5/11/2020 Pb-212 4.06E+02 3.18E+Ol 4.0IE+Ol SE 08 511615002 5/11/2020 Pb-214 2.71E+02 3.53E+Ol 4.61E+Ol SE 08 511615002 5/11/2020 Ra-226 3.04E+02 3.43E+Ol 4.62E+Ol SE 08 511615002 5/11/2020 Ru-103 -1.13E+Ol 7.32E+OO 2.22E+Ol u SE 08 511615002 5/11/2020 Ru-106 7.58E+Ol 6.12E+Ol 2.11E+02 u SE 08 511615002 5/11/2020 Sb-124 7.38E+OO l.43E+Ol 4.84E+Ol u SE 08 511615002 5/11/2020 Sb-125 l.73E+Ol l.54E+Ol 5.47E+Ol u SE 08 511615002 5/11/2020 Se-75 l.41E+OO 8.14E+OO 2.71E+Ol u SE 08 511615002 5/11/2020 Th-228 4.06E+02 3.18E+Ol 4.0IE+Ol SE 08 511615002 5/11/2020 Th-230 3.04E+02 3.43E+Ol 4.62E+Ol SE 08 511615002 5/11/2020 Tl-208 l.IOE+02 l.62E+Ol 2.13E+Ol SE 08 511615002 5/11/2020 Zn-65 4.16E+Ol 2.24E+Ol 6.59E+Ol u SE 08 511615002 5/11/2020 Zr-95 -1.0IE+Ol l.41E+Ol 4.50E+Ol u SE 08 528391002 11/19/2020 Ac-228 4.15E+02 l.05E+02 l.59E+02 SE 08 528391002 11/19/2020 Ag-108m 3.60E+OO 8.91E+OO 3.18E+Ol u SE 08 528391002 11/19/2020 Ag-llOm 3.51E+Ol 3.04E+Ol 6.32E+Ol u SE 08 528391002 11119/2020 Ba-140 l.22E+02 2.14E+02 7.53E+02 u SE 08 528391002 11/19/2020 Be-7 -1.88E+Ol l.15E+02 3.96E+02 u SE 08 528391002 11/19/2020 Bi-214 2.45E+02 5.12E+Ol 7.36E+Ol SE 08 528391002 11/19/2020 Ce-141 -7.53E+Ol 3.32E+Ol 7.65E+Ol u SE 08 528391002 11/19/2020 Ce-144 9.60E+OO 5.98E+Ol 2.13E+02 u SE 08 528391002 11/19/2020 Co-57 6.67E+OO 7.65E+OO 2.77E+Ol u SE 08 528391002 11/19/2020 Co-58 2.97E+OO 1.46E+Ol 4.85E+Ol u SE 08 528391002 11119/2020 Co-60 -1.87E+Ol l.59E+Ol 4.48E+Ol u SE 08 528391002 11/19/2020 Cr-51 5.81E+Ol l.49E+02 5.48E+02 u SE 08 528391002 11/19/2020 Cs-134 2.71E+Ol 2.88E+Ol 4.84E+Ol u SE 08 528391002 11/19/2020 Cs-137 -4.35E+OO l.19E+Ol 3.84E+Ol u SE 08 528391002 11/19/2020 Fe-59 -2.05E+OO 4.42E+Ol l.49E+02 u SE 08 528391002 11/19/2020 1-131 l.88E+02 l.60E+02 5.80E+02 u SE 08 528391002 11/19/2020 K-40 l.89E+04 l.18E+03 3.19E+02 SE 08 528391002 11/19/2020 La-140 -1.40E+02 8.45E+Ol 1.42E+02 u SE 08 528391002 11/19/2020 Mn-54 l.37E+Ol 1.46E+Ol 4.95E+Ol u SE 08 528391002 11/19/2020 Nb-95 O.OOE+OO 3.68E+Ol 5.02E+Ol u SE 08 528391002 11/19/2020 Pb-212 4.78E+02 4.55E+Ol 5.47E+Ol SE 08 528391002 11/19/2020 Pb-214 l.77E+02 6.19E+Ol 7.90E+Ol SE 08 528391002 11/19/2020 Ra-226 2.45E+02 5.12E+Ol 7.36E+Ol SE 08 528391002 11/19/2020 Ru-103 l.46E+Ol l.48E+Ol 5.32E+Ol u SE 08 528391002 11/19/2020 Ru-106 -3.97E+Ol l.OOE+02 3.26E+02 u SE 08 528391002 11/19/2020 Sb-124 -5.73E+Ol 3.71E+Ol 7.77E+Ol u SE 08 528391002 11/19/2020 Sb-125 2.27E+Ol 2.84E+Ol l.02E+02 u SE 08 528391002 11/19/2020 Se-75 -2.12E+OO l.50E+Ol 4.54E+Ol u SE 08 528391002 11/19/2020 Th-228 4.78E+02 4.55E+Ol 5.47E+Ol SE 08 528391002 11/19/2020 Th-230 2.45E+02 5.12E+Ol 7.36E+Ol SE 08 528391002 11/19/2020 Tl-208 1.23E+02 2.99E+Ol 3.70E+Ol SE 08 528391002 11/19/2020 Zn-65 l.12E+Ol 3.98E+Ol 1.04E+02 u SE 08 528391002 11/19/2020 Zr-95 l.26E+Ol 3.09E+Ol 1.05E+02 u 202

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/kg) (pCi/kg) (pCi/kg)

SE 52 511608002 5/14/2020 Ac-228 l.23E+03 l.28E+02 1.21E+02 SE 52 511608002 5/14/2020 Ag-108m -2.38E+OO 7.20E+OO 2.49E+Ol u SE 52 511608002 5/14/2020 Ag-1 !0m -6.08E+OO l.28E+Ol 4.29E+Ol u SE 52 511608002 5/14/2020 Ba-140 9.40E+Ol 7.90E+Ol l.63E+02 u SE 52 511608002 5/14/2020 Be-7 -2.57E+OO 7.20E+Ol 2.50E+02 u SE 52 511608002 5/14/2020 Bi-214 7.69E+02 5.82E+Ol 5.89E+Ol SE 52 511608002 5/14/2020 Ce-141 -l.76E+Ol 1.44E+Ol 4.36E+Ol u SE 52 511608002 5/14/2020 Ce-144 6.67E+Ol 4.69E+Ol l.66E+02 u SE 52 511608002 5/14/2020 Co-57 9.40E+OO 5.85E+OO 2.06E+Ol u SE 52 511608002 5/14/2020 Co-58 2.04E+Ol l.03E+Ol 3.50E+Ol u SE 52 511608002 5/14/2020 Co-60 -l.51E+Ol l.13E+Ol 3.16E+Ol u SE 52 511608002 5/14/2020 Cr-51 -4.72E+Ol 7.27E+Ol 2.56E+02 u SE 52 511608002 5/14/2020 Cs-134 O.OOE+OO 2.18E+Ol 4.27E+Ol u SE 52 511608002 5/14/2020 Cs-137 -l.86E+Ol 1.07E+Ol 2.94E+Ol u SE 52 511608002 5/14/2020 Fe-59 -l.45E+Ol 2.18E+Ol 6.96E+Ol u SE 52 511608002 5/14/2020 I-131 -9.02E+OO l.55E+Ol 5.38E+Ol u SE 52 511608002 5/14/2020 K-40 l.46E+04 8.63E+02 3.05E+02 SE 52 511608002 5/14/2020 La-140 -3.IOE+OO l.74E+Ol 4.98E+Ol u SE 52 511608002 5/14/2020 Mn-54 6.63E+OO 9.70E+OO 3.33E+Ol u SE 52 511608002 5/14/2020 Nb-95 2.04E+Ol l.18E+Ol 3.70E+Ol u SE 52 511608002 5/14/2020 Pb-212 l.17E+03 6.30E+Ol 4.81E+Ol SE 52 511608002 5/14/2020 Pb-214 9.00E+02 6.26E+Ol 6.40E+Ol SE 52 511608002 5/14/2020 Ra-226 7.69E+02 5.82E+Ol 5.89E+Ol SE 52 511608002 5/14/2020 Ru-103 6.05E+OO 9.36E+OO 3.28E+Ol u SE 52 511608002 5/14/2020 Ru-106 5.90E+Ol 8.12E+Ol 2.78E+02 u SE 52 511608002 5/14/2020 Sb-124 3.02E+Ol l.93E+Ol 6.95E+Ol u SE 52 511608002 5/14/2020 Sb-125 -l.97E+Ol 2.14E+Ol 7.07E+Ol u SE 52 511608002 5/14/2020 Se-75 8.72E+OO 1.1 IE+Ol 3.48E+Ol u SE 52 511608002 5/14/2020 Th-228 l.17E+03 6.30E+Ol 4.81E+Ol SE 52 511608002 5/14/2020 Th-230 7.69E+02 5.82E+Ol 5.89E+Ol SE 52 511608002 5/14/2020 Tl-208 3.69E+02 2.67E+Ol 2.85E+Ol SE 52 511608002 5/14/2020 Zn-65 -3.09E+Ol 2.53E+Ol 6.36E+Ol u SE 52 511608002 5/14/2020 Zr-95 -2.29E+Ol 2.07E+Ol 6.18E+Ol u SE 52 529874002 12/9/2020 Ac-228 4.32E+03 3.39E+02 2.24E+02 SE 52 529874002 12/9/2020 Ag-108m -3.69E+OO l.77E+Ol 6.34E+Ol u SE 52 529874002 12/9/2020 Ag-I !Om 5.60E-Ol 2.85E+Ol 9.51E+Ol u SE 52 529874002 12/9/2020 Ba-140 7.35E+Ol 2.71E+02 9.66E+02 u SE 52 529874002 12/9/2020 Be-7 3.90E+02 5.15E+02 6.97E+02 u SE 52 529874002 12/9/2020 Bi-214 2.39E+03 l.66E+02 l.46E+02 SE 52 529874002 12/9/2020 Ce-141 -5.71E+Ol 4.60E+Ol l.55E+02 u SE 52 529874002 12/9/2020 Ce-144 4.62E+Ol l.14E+02 4.20E+02 u SE 52 529874002 12/9/2020 Co-57 -l.73E+Ol l.50E+Ol 5.17E+Ol u SE 52 529874002 12/9/2020 Co-58 -3.62E+OO 2.57E+Ol 8.57E+Ol u SE 52 529874002 12/9/2020 Co-60 4.94E+OO 2.12E+Ol 7.35E+Ol u SE 52 529874002 12/9/2020 Cr-51 4.31E+02 2.84E+02 9.52E+02 u SE 52 529874002 12/9/2020 Cs-134 O.OOE+OO 8.43E+Ol l.37E+02 u SE 52 529874002 12/9/2020 Cs-137 7.26E+OO 2.36E+Ol 7.41E+Ol u SE 52 529874002 12/9/2020 Fe-59 6.43E+OO 5.97E+Ol 2.09E+02 u SE 52 529874002 12/9/2020 1-131 l.55E+02 l.60E+02 5.03E+02 u SE 52 529874002 12/9/2020 K-40 l.26E+04 9.85E+02 5.58E+02 203

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/kg) (pCi/kg) (pCi/kg)

SE 52 529874002 12/9/2020 La-140 2.28E+Ol 8.41E+Ol 2.56E+02 u SE 52 529874002 12/9/2020 Mn-54 2.81E+Ol 2.60E+Ol 8.92E+Ol u SE 52 529874002 12/9/2020 Nb-95 l.72E+Ol 3.06E+Ol 9.55E+Ol u SE 52 529874002 12/9/2020 Pb-212 4.54E+03 2.35E+02 l.23E+02 SE 52 529874002 12/9/2020 Pb-214 3.17E+03 2.00E+02 4.66E+02 SE 52 529874002 12/9/2020 Ra-226 2.39E+03 l.66E+02 l.46E+02 SE 52 529874002 12/9/2020 Ru-103 -4.86E+OO 2.47E+Ol 8.69E+Ol u SE 52 529874002 12/9/2020 Ru-106 l.38E+02 l.99E+02 7.04E+02 u SE 52 529874002 12/9/2020 Sb-124 -2.72E+Ol 5.76E+Ol l.78E+02 u SE 52 529874002 12/9/2020 Sb-125 -3.84E+Ol 5.61E+Ol l.95E+02 u SE 52 529874002 12/9/2020 Se-75 -l.12E+Ol 2.64E+Ol 8.87E+Ol u SE 52 529874002 12/9/2020 Th-228 4.54E+03 2.35E+02 l.23E+02 SE 52 529874002 12/9/2020 Th-230 2.39E+03 l.66E+02 l.46E+02 SE 52 529874002 12/9/2020 Tl-208 l.31E+03 9.57E+Ol 7.45E+Ol SE 52 529874002 12/9/2020 Zn-65 -2.45E+Ol 5.52E+Ol l.61E+02 u SE 52 529874002 12/9/2020 Zr-95 5.68E+Ol 5.65E+Ol l.96E+02 u SE 57 511615003 5/18/2020 Ac-228 3.90E+02 7.44E+Ol l.l 1E+02 SE 57 511615003 5/18/2020 Ag-108m l.40E+OO 5.76E+OO 2.03E+Ol u SE 57 511615003 5/18/2020 Ag-llOm O.OOE+OO 4.32E+Ol 4.18E+Ol u SE 57 511615003 5/18/2020 Ba-140 l.OIE+Ol 2.97E+Ol l.03E+02 u SE 57 511615003 5/18/2020 Be-7 2.16E+02 8.54E+Ol l.86E+02 SE 57 511615003 5/18/2020 Bi-214 2.63E+02 3.74E+Ol 5.13E+Ol SE 57 511615003 5/18/2020 Ce-141 9.08E+OO l.07E+Ol 3.43E+Ol u SE 57 511615003 5/18/2020 Ce-144 -1.1 lE+Ol 3.95E+Ol l.36E+02 u SE 57 511615003 5/18/2020 Co-57 l.IOE+Ol 5.48E+OO l.80E+Ol u SE 57 511615003 5/18/2020 Co-58 -5.77E+OO 7.54E+OO 2.34E+Ol u SE 57 511615003 5/18/2020 Co-60 4.75E-Ol 9.47E+OO 2.82E+Ol u SE 57 511615003 5/18/2020 Cr-51 4.84E+Ol 5.65E+Ol 2.04E+02 u SE 57 511615003 5/18/2020 Cs-134 O.OOE+OO 2.62E+Ol 3.57E+Ol u SE 57 511615003 5/18/2020 Cs-137 l.05E+OO 7.71E+OO 2.61E+Ol u SE 57 511615003 5/18/2020 Fe-59 -2.86E+OO 2.00E+Ol 6.55E+Ol u SE 57 511615003 5/18/2020 I-131 9.62E+OO 9.08E+OO 2.96E+Ol u SE 57 511615003 5/18/2020 K-40 2.15E+04 l.27E+03 l.78E+02 SE 57 511615003 5/18/2020 La-140 -8.05E+OO 8.36E+OO 2.40E+Ol u SE 57 511615003 5/18/2020 Mn-54 -6.68E+OO 8.43E+OO 2.61E+Ol u SE 57 511615003 5/18/2020 Nb-95 -6.59E+OO 7.93E+OO 2.47E+Ol u SE 57 511615003 5/18/2020 Pb-212 4.50E+02 3.46E+Ol 3.88E+Ol SE 57 511615003 5/18/2020 Pb-214 3.86E+02 4.15E+Ol 1.02E+02 SE 57 511615003 5/18/2020 Ra-226 2.63E+02 3.74E+Ol 5.13E+Ol SE 57 511615003 5/18/2020 Ru-103 8.03E+OO 6.55E+OO 2.29E+Ol u SE 57 511615003 5/18/2020 Ru-106 5.95E+Ol 6.35E+Ol 2.20E+02 u SE 57 511615003 5/18/2020 Sb-124 5.51E+OO l.28E+Ol 4.39E+Ol u SE 57 511615003 5/18/2020 Sb-125 9.59E-Ol l.85E+Ol 6.48E+Ol u SE 57 511615003 5/18/2020 Se-75 -7.56E+OO 8.27E+OO 2.72E+Ol u SE 57 511615003 5/18/2020 Th-228 4.50E+02 3.46E+Ol 3.88E+Ol SE 57 511615003 5/18/2020 Th-230 2.63E+02 3.74E+Ol 5.13E+Ol SE 57 511615003 5/18/2020 Tl-208 l.l 1E+02 l.88E+Ol 2.66E+Ol SE 57 511615003 5/18/2020 Zn-65 -l.53E+Ol 2.32E+Ol 6.66E+Ol u SE 57 511615003 5/18/2020 Zr-95 l.30E+Ol l.35E+Ol 4.61E+Ol u 204

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/kg) (pCi/kg) (pCi/kg)

SE 57 528391003 11/18/2020 Ac-228 2.90E+02 1.07E+02 1.29E+02 SE 57 528391003 11/18/2020 Ag-108m -3.67E+OO 8.06E+OO 2.69E+Ol u SE 57 528391003 11/18/2020 Ag-llOm -2.38E+OO l.53E+Ol 4.87E+Ol u SE 57 528391003 11/18/2020 Ba-140 2.86E+02 2.12E+02 7.44E+02 u SE 57 528391003 11/18/2020 Be-7 3.55E+02 2.28E+02 3.64E+02 u SE 57 528391003 11/18/2020 Bi-214 2.64E+02 6.08E+Ol 8.26E+Ol SE 57 528391003 11/18/2020 Ce-141 -6.93E+OO 2.46E+Ol 8.21E+Ol u SE 57 528391003 11/18/2020 Ce-144 -4.67E+Ol 6.20E+Ol 2.01E+02 u SE 57 528391003 11/18/2020 Co-57 -2.47E+OO 7.19E+OO 2.42E+Ol u SE 57 528391003 11/18/2020 Co-58 4.52E+OO 1.37E+Ol 4.60E+Ol u SE 57 528391003 11/18/2020 Co-60 -l.07E+Ol l.50E+Ol 4.64E+Ol u SE 57 528391003 11/18/2020 Cr-51 l.95E+02 l.71E+02 6.15E+02 u SE 57 528391003 11/18/2020 Cs-134 3.68E+Ol 2.06E+Ol 5.24E+Ol u SE 57 528391003 11/18/2020 Cs-13 7 l.OOE+Ol 1.24E+Ol 3.93E+Ol u SE 57 528391003 11/18/2020 Fe-59 -3.30E+Ol 4.02E+Ol 1.26E+02 u SE 57 528391003 11/18/2020 1-131 l.52E+02 1.52E+02 5.46E+02 u SE 57 528391003 11/18/2020 K-40 l.88E+04 l.18E+03 3.66E+02 SE 57 528391003 11/18/2020 La-140 l.94E+02 8.35E+Ol 3.03E+02 u SE 57 528391003 11/18/2020 Mn-54 7.15E+OO l.38E+Ol 4.64E+Ol u SE 57 528391003 11/18/2020 Nb-95 -8.94E+OO 1.79E+Ol 5.44E+Ol u SE 57 528391003 11/18/2020 Pb-212 4.52E+02 4.49E+Ol 5.50E+Ol SE 57 528391003 11/18/2020 Pb-214 3.74E+02 6.00E+Ol l.50E+02 SE 57 528391003 11/18/2020 Ra-226 2.64E+02 6.08E+Ol 8.26E+Ol SE 57 528391003 11/18/2020 Ru-103 -8.92E-01 1.78E+Ol 6.05E+Ol u SE 57 528391003 11/18/2020 Ru-106 l.64E+02 l.10E+02 3.80E+02 u SE 57 528391003 11/18/2020 Sb-124 l.29E+Ol 2.25E+Ol 8.14E+Ol u SE 57 528391003 11/18/2020 Sb-125 -3.34E+Ol 2.70E+Ol 8.22E+Ol u SE 57 528391003 11/18/2020 Se-75 9.09E+OO l.28E+Ol 4.68E+Ol u SE 57 528391003 11/18/2020 Th-228 4.52E+02 4.49E+Ol 5.50E+Ol SE 57 528391003 11/18/2020 Th-230 2.64E+02 6.08E+Ol 8.26E+Ol SE 57 528391003 11/18/2020 Tl-208 1.57E+02 3.02E+Ol 3.95E+Ol SE 57 528391003 11 /18/2020 Zn-65 -7.44E+Ol 4.09E+Ol 9.68E+Ol u SE 57 528391003 11/18/2020 Zr-95 2.03E+Ol 2.81E+Ol 9.62E+Ol u 205

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/kg) (pCi/kg) (pCi/kg)

TF 02 514168001 6/18/2020 Ac-228 4.95E+OO 9.43E+OO 2.73E+Ol u TF 02 514168001 6/18/2020 Ag-108m 9.39E-Ol l.52E+OO 4.94E+OO u TF 02 514168001 6/18/2020 Ag-llOm -l.29E+OO 2.75E+OO 7.48E+OO u TF 02 514168001 6/18/2020 Ba-140 -2.32E+OO 6.97E+OO 2.32E+Ol u TF 02 514168001 6/18/2020 Be-7 -l.96E+Ol l.55E+Ol 4.39E+Ol u TF 02 514168001 6/18/2020 Ce-141 -5.42E+OO 3.IOE+OO 7.53E+OO u TF 02 514168001 6/18/2020 Ce-144 l.30E+Ol 9.60E+OO 3.llE+Ol u TF 02 514168001 6/18/2020 Co-57 -5.53E-Ol l.17E+OO 3.94E+OO u TF 02 514168001 6/18/2020 Co-58 l.49E+OO l.60E+OO 5.45E+OO u TF 02 514168001 6/18/2020 Co-60 5.78E-Ol l.47E+OO 5.09E+OO u TF 02 514168001 6/18/2020 Cr-51 -3.13E+OO l.38E+Ol 4.45E+Ol u TF 02 514168001 6/18/2020 Cs-134 -l.80E-Ol l.85E+OO 6.07E+OO u TF 02 514168001 6/18/2020 Cs-137 l.35E+OO l.81E+OO 6.17E+OO u TF 02 514168001 6/18/2020 Fe-59 8.25E+OO 9.09E+OO l.20E+Ol u TF 02 514168001 6/18/2020 I-131 l.77E+OO 2.33E+OO 7.68E+OO u TF 02 514168001 6/18/2020 K-40 l.31E+03 l.OOE+02 5.96E+Ol TF 02 514168001 6/18/2020 La-140 4.33E-Ol 2.33E+OO 7.83E+OO u TF 02 514168001 6/18/2020 Mn-54 -l.26E+OO l.82E+OO 5.64E+OO u TF 02 514168001 6/18/2020 Nb-95 7.46E-Ol l.68E+OO 5.68E+OO u TF 02 514168001 6/18/2020 Ru-103 l.69E+OO 1.53E+OO 5.02E+OO u TF 02 514168001 6/18/2020 Ru-106 -3.07E+Ol 2.05E+Ol 4.70E+Ol u TF 02 514168001 6/18/2020 Sb-124 -l.07E+Ol 5.0IE+OO l.04E+Ol u TF 02 514168001 6/18/2020 Sb-125 l.80E+OO 4.22E+OO l.38E+Ol u TF 02 514168001 6/18/2020 Se-75 -7.03E-Ol l.87E+OO 6.05E+OO u TF 02 514168001 6/18/2020 Th-228 5.1 IE+OO 5.05E+OO 8.19E+OO u TF 02 514168001 6/18/2020 Zn-65 -4.74E+OO 4.32E+OO l.23E+Ol u TF 02 514168001 6/18/2020 Zr-95 -4.96E-Ol 2.92E+OO 9.56E+OO u TF 02 516040001 7/14/2020 Ac-228 2.53E+Ol l.81E+Ol 4.07E+Ol u TF 02 516040001 7/14/2020 Ag-108m -4.0IE+OO 2.15E+OO 5.06E+OO u TF 02 516040001 7/14/2020 Ag-llOm -4.87E+OO 3.45E+OO 8.93E+OO u TF 02 516040001 7/14/2020 Ba-140 -4.06E+OO 9.74E+OO 3.18E+Ol u TF 02 516040001 7/14/2020 Be-7 l.29E+Ol l.81E+Ol 6.0IE+Ol u TF 02 516040001 7/14/2020 Ce-141 9.64E-Ol 3.59E+OO 1.23E+Ol u TF 02 516040001 7/14/2020 Ce-144 -5.28E+OO l.44E+Ol 4.60E+Ol u TF 02 516040001 7/14/2020 Co-57 l.54E+OO l.84E+OO 5.84E+OO u TF 02 516040001 7/14/2020 Co-58 -l.69E+OO 2.09E+OO 6.14E+OO u TF 02 516040001 7/14/2020 Co-60 l.13E+OO 2.30E+OO 8.14E+OO u TF 02 516040001 7/14/2020 Cr-51 l.05E+Ol l.84E+Ol 6.17E+Ol u TF 02 516040001 7/14/2020 Cs-134 l.61E+OO 2.59E+OO 8.91E+OO u TF 02 516040001 7/14/2020 Cs-13 7 5.93E+OO 2.94E+OO 9.44E+OO u TF 02 516040001 7/14/2020 Fe-59 3.78E+OO 5.02E+OO l.72E+Ol u TF 02 516040001 7/14/2020 I-131 -4.20E+OO 3.69E+OO l.06E+Ol u TF 02 516040001 7/14/2020 K-40 6.19E+02 7.61E+Ol 7.27E+Ol TF 02 516040001 7/14/2020 La-140 -5.71E-Ol 3.60E+OO l.16E+Ol u TF 02 516040001 7/14/2020 Mn-54 2.74E-02 2.43E+OO 7.98E+OO u TF 02 516040001 7/14/2020 Nb-95 5.02E+OO 2.77E+OO 8.98E+OO u TF 02 516040001 7/14/2020 Ru-103 -4.26E+OO 2.63E+OO 6.52E+OO u TF 02 516040001 7/14/2020 Ru-106 -2.31E+Ol 2.19E+Ol 5.43E+Ol u TF 02 516040001 7/14/2020 Sb-124 -5.80E+OO 5.27E+OO l.31E+Ol u TF 02 516040001 7/14/2020 Sb-125 -l.53E+Ol 7.33E+OO l.65E+Ol u 206

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/kg) (pCi/kg) (pCi/kg)

TF 02 516040001 7/14/2020 Se-75 -6.78E-01 2.85E+OO 9.27E+OO u TF 02 516040001 7/14/2020 Th-228 -9.73E+OO 5.77E+OO 1.55E+Ol u TF 02 516040001 7/14/2020 Zn-65 l.84E+OO 5.76E+OO l.78E+Ol u TF 02 516040001 7/14/2020 Zr-95 7.44E-01 3.57E+OO l.21E+Ol u TF 02 518831001 8/12/2020 Ac-228 9.31E+OO 1.95E+Ol 4.33E+Ol u TF 02 518831001 8/12/2020 Ag-108m 6.18E-01 2.08E+OO 6.82E+OO u TF 02 518831001 8/12/2020 Ag-llOm 1.14E-01 3.28E+OO l.08E+Ol u TF 02 518831001 8/12/2020 Ba-140 7.08E+OO l.02E+Ol 3.40E+Ol u TF 02 518831001 8/12/2020 Be-7 l.69E+Ol l.93E+Ol 6.45E+Ol u TF 02 518831001 8/12/2020 Ce-141 9.75E-01 3.53E+OO 1.IOE+Ol u TF 02 518831001 8/12/2020 Ce-144 l.47E+OO l.22E+Ol 4.19E+Ol u TF 02 518831001 8/12/2020 Co-57 3.84E-01 l.63E+OO 5.63E+OO u TF 02 518831001 8/12/2020 Co-58 -2.28E-01 2.40E+OO 7.88E+OO u TF 02 518831001 8/12/2020 Co-60 -4.02E-01 3.llE+OO l.04E+Ol u TF 02 518831001 8/12/2020 Cr-51 l.41E+Ol 1.75E+Ol 5.96E+Ol u TF 02 518831001 8/12/2020 Cs-134 l.94E+OO 2.97E+OO l.02E+Ol u TF 02 518831001 8/12/2020 Cs-137 -4.39E-01 2.42E+OO 8.02E+OO u TF 02 518831001 8/12/2020 Fe-59 3.72E+OO 6.22E+OO 2.IOE+Ol u TF 02 518831001 8/12/2020 1-131 9.24E+OO 1.0IE+Ol l.30E+Ol u TF 02 518831001 8/12/2020 K-40 2.08E+03 l.75E+02 8.21E+Ol TF 02 518831001 8/12/2020 La-140 -4.56E+OO 3.99E+OO 9.98E+OO u TF 02 518831001 8/12/2020 Mn-54 2.13E+OO 2.54E+OO 8.80E+OO u TF 02 518831001 8/12/2020 Nb-95 3.23E+OO 3.63E+OO 5.88E+OO u TF 02 518831001 8/12/2020 Ru-103 -2.81E+OO 2.72E+OO 7.74E+OO u TF 02 518831001 8/12/2020 Ru-106 4.67E+OO 2.08E+Ol 7.14E+Ol u TF 02 518831001 8/12/2020 Sb-124 5.16E+OO 3.99E+OO l.59E+Ol u TF 02 518831001 8/12/2020 Sb-125 9.75E-01 6.68E+OO 2.17E+Ol u TF 02 518831001 8/12/2020 Se-75 -6.36E-01 2.77E+OO 9.06E+OO u TF 02 518831001 8/12/2020 Th-228 -6.18E+OO 4.74E+OO l.47E+Ol u TF 02 518831001 8/12/2020 Zn-65 7.04E+OO 5.88E+OO 2.05E+Ol u TF 02 518831001 8/12/2020 Zr-95 2.IOE+OO 3.68E+OO l.28E+Ol u TF 03 514168002 6/18/2020 Ac-228 -6.36E+OO 8.08E+OO 2.29E+Ol u TF 03 514168002 6/18/2020 Ag-108m 8.94E-01 1.15E+OO 3.60E+OO u TF 03 514168002 6/18/2020 Ag-llOm 1.22E+OO l.90E+OO 6.28E+OO u TF 03 514168002 6/18/2020 Ba-140 -3.44E+OO 5.09E+OO l.60E+Ol u TF 03 514168002 6/18/2020 Be-7 l.26E+Ol 1.14E+Ol 3.87E+Ol u TF 03 514168002 6/18/2020 Ce-141 -5.09E+OO 2.64E+OO 5.87E+OO u TF 03 514168002 6/18/2020 Ce-144 6.32E+OO 7.86E+OO 2.58E+Ol u TF 03 514168002 6/18/2020 Co-57 2.1 IE+OO 1.43E+OO 3.19E+OO u TF 03 514168002 6/18/2020 Co-58 9.73E-01 l.67E+OO 5.48E+OO u TF 03 514168002 6/18/2020 Co-60 8.64E-01 1.50E+OO 5.18E+OO u TF 03 514168002 6/18/2020 Cr-51 9.84E+OO 1.60E+Ol 3.44E+Ol u TF 03 514168002 6/18/2020 Cs-134 2.44E-01 l.33E+OO 4.34E+OO u TF 03 514168002 6/18/2020 Cs-137 3.85E+OO l.64E+OO 4.21E+OO u TF 03 514168002 6/18/2020 Fe-59 6.36E-01 2.71E+OO 9.28E+OO u TF 03 514168002 6/18/2020 1-131 -1.80E+OO l.62E+OO 5.0IE+OO u TF 03 514168002 6/18/2020 K-40 1.53E+03 1.11E+02 4.49E+Ol TF 03 514168002 6/18/2020 La-140 -3.75E+OO 2.62E+OO 5.92E+OO u TF 03 514168002 6/18/2020 Mn-54 -2.36E-01 l.46E+OO 4.62E+OO u 207

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/kg) (pCi/kg) (pCi/kg)

TF 03 514168002 6/18/2020 Nb-95 7.85E-01 1.20E+OO 4.02E+OO u TF 03 514168002 6/18/2020 Ru-103 1.52E-01 1.37E+OO 4.58E+OO u TF 03 514168002 6/18/2020 Ru-106 6.07E+OO 1.08E+Ol 3.62E+Ol u TF 03 514168002 6/18/2020 Sb-124 1.95E+OO 2.88E+OO 1.00E+Ol u TF 03 514168002 6/18/2020 Sb-125 4.77E-01 3.73E+OO 1.13E+Ol u TF 03 514168002 6/18/2020 Se-75 3.12E+OO 1.76E+OO 5.45E+OO u TF 03 514168002 6/18/2020 Th-228 2.52E+OO 5.32E+OO 8.84E+OO u TF 03 514168002 6/18/2020 Zn-65 l.82E-02 3.07E+OO 1.03E+Ol u TF 03 514168002 6/18/2020 Zr-95 -5.81E-01 2.25E+OO 7.llE+OO u TF 03 516040002 7/14/2020 Ac-228 7.51E-01 l.13E+Ol 3.86E+Ol u TF 03 516040002 7/14/2020 Ag-108m 4.19E-01 1.51E+OO 5.19E+OO u TF 03 516040002 7/14/2020 Ag-llOm -7.17E-01 3.llE+OO 9.77E+OO u TF 03 516040002 7/14/2020 Ba-140 -6.90E+OO 9.25E+OO 2.82E+Ol u TF 03 516040002 7/14/2020 Be-7 2.20E+Ol 1.90E+Ol 6.63E+Ol u TF 03 516040002 7/14/2020 Ce-141 l.85E+OO 3.20E+OO 9.83E+OO u TF 03 516040002 7/14/2020 Ce-144 1.llE+Ol 1.22E+Ol 4.03E+Ol u TF 03 516040002 7/14/2020 Co-57 O.OOE+OO 2.55E+OO 4.37E+OO u TF 03 516040002 7/14/2020 Co-58 -1.95E+OO 2.66E+OO 7.93E+OO u TF 03 516040002 7/14/2020 Co-60 6.19E-01 2.84E+OO 1.06E+Ol u TF 03 516040002 7/14/2020 Cr-51 2.34E+Ol 1.95E+Ol 6.83E+Ol u TF 03 516040002 7/14/2020 Cs-134 3.lOE+OO 2.91E+OO 9.21E+OO u TF 03 516040002 7/14/2020 Cs-137 2.67E+OO 2.47E+OO 8.53E+OO u TF 03 516040002 7/14/2020 Fe-59 -4.31E-01 6.1 lE+OO l.93E+Ol u TF 03 516040002 7/14/2020 I-131 1.15E+OO 4.llE+OO 1.42E+Ol u TF 03 516040002 7/14/2020 K-40 2.25E+03 1.58E+02 6.0lE+Ol TF 03 516040002 7/14/2020 La-140 1.17E+OO 2.86E+OO 1.0lE+Ol u TF 03 516040002 7/14/2020 Mn-54 6.32E-01 2.14E+OO 7.llE+OO u TF 03 516040002 7/14/2020 Nb-95 3.27E+OO 2.52E+OO 8.70E+OO u TF 03 516040002 7114/2020 Ru-103 -1.1 lE+OO 2.12E+OO 6.79E+OO u TF 03 516040002 7/14/2020 Ru-106 -2.74E+Ol 2.06E+Ol 5.69E+Ol u TF 03 516040002 7/14/2020 Sb-124 1.77E+OO 3.64E+OO 1.32E+Ol u TF 03 516040002 7/14/2020 Sb-125 -8.46E-01 4.91E+OO 1.64E+Ol u TF 03 516040002 7/14/2020 Se-75 1.81E+OO 2.40E+OO 8.23E+OO u TF 03 516040002 7/14/2020 Th-228 1.67E+OO 4.53E+OO 1.35E+Ol u TF 03 516040002 7/14/2020 Zn-65 -1.46E+OO 5.82E+OO 1.57E+Ol u TF 03 516040002 7/14/2020 Zr-95 -6.65E-01 3.91E+OO 1.25E+Ol u TF 03 518831002 8/12/2020 Ac-228 -4.44E+OO 1.28E+Ol 4.12E+Ol u TF 03 518831002 8/12/2020 Ag-108m 1.25E+OO 2.30E+OO 7.94E+OO u TF 03 518831002 8/12/2020 Ag-llOm 7.19E-01 4.03E+OO 1.31E+Ol u TF 03 518831002 8/12/2020 Ba-140 1.34E+Ol 1.1 lE+Ol 3.65E+Ol u TF 03 518831002 8/12/2020 Be-7 2.80E+Ol 2.09E+Ol 7.33E+Ol u TF 03 518831002 8/12/2020 Ce-141 -4.14E+OO 5.03E+OO 1.45E+Ol u TF 03 518831002 8/12/2020 Ce-144 4.24E+OO l.52E+Ol 4.94E+Ol u TF 03 518831002 8/12/2020 Co-57 -1.05E+OO 2.1 lE+OO 6.57E+OO u TF 03 518831002 8/12/2020 Co-58 -2.24E+OO 2.80E+OO 8.09E+OO u TF 03 518831002 8/12/2020 Co-60 -3.48E-01 2.93E+OO 9.63E+OO u TF 03 518831002 8/12/2020 Cr-51 7.03E-01 2.16E+Ol 7.36E+Ol u TF 03 518831002 8/12/2020 Cs-134 7.49E-01 2.78E+OO 9.22E+OO u TF 03 518831002 8/12/2020 Cs-137 2.45E-01 3.15E+OO 1.04E+Ol u 208

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/kg) (pCi/kg) (pCi/kg)

TF 03 518831002 8/12/2020 Fe-59 -9.85E+OO 6.46E+OO 1.70E+Ol u TF 03 518831002 8/12/2020 l-131 -2.90E+OO 4.12E+OO l.32E+Ol u TF 03 518831002 8/12/2020 K-40 2.58E+03 2.02E+02 8.80E+Ol TF 03 518831002 8/12/2020 La-140 -6.08E+OO 3.79E+OO 6.94E+OO u TF 03 518831002 8/12/2020 Mn-54 4.25E+OO 3.13E+OO l.07E+Ol u TF 03 518831002 8/12/2020 Nb-95 6.90E-01 2.85E+OO 9.42E+OO u TF 03 518831002 8/12/2020 Ru- I 03 -2.13E+OO 3.02E+OO 9.42E+OO u TF 03 518831002 8/12/2020 Ru-106 -1.09E+Ol 2.41E+Ol 7.54E+Ol u TF 03 518831002 8/12/2020 Sb-124 6.08E+OO 6.41E+OO 2.36E+Ol u TF 03 518831002 8/12/2020 Sb-125 5.0lE-01 6.51E+OO 2.20E+Ol u TF 03 518831002 8/12/2020 Se-75 6.62E-Ol 3.25E+OO 1.13E+Ol u TF 03 518831002 8/12/2020 Th-228 -1.25E+OO 5.57E+OO l.76E+Ol u TF 03 518831002 8/12/2020 Zn-65 2. llE+OO 6.24E+OO 2.17E+Ol u TF 03 518831002 8/12/2020 Zr-95 2.13E+OO 6.08E+OO l.82E+Ol u TF 06 514168003 6/18/2020 Ac-228 1.77E+Ol l.35E+Ol 2.33E+Ol u TF 06 514168003 6/18/2020 Ag-108m -1.41E+OO l.27E+OO 3.89E+OO u TF 06 514168003 6/18/2020 Ag-llOm -4.84E-Ol l.75E+OO 5.48E+OO u TF 06 514168003 6/18/2020 Ba-140 -2.73E+OO 5.63E+OO l.80E+Ol u TF 06 514168003 6/18/2020 Be-7 1.59E+Ol l.23E+Ol 4.15E+Ol u TF 06 514168003 6118/2020 Ce-141 6.98E-01 2.23E+OO 7.14E+OO u TF 06 514168003 6118/2020 Ce-144 -1.14E+OO 8.56E+OO 2.72E+Ol u TF 06 514168003 6/18/2020 Co-57 l.39E+OO l.24E+OO 3.96E+OO u TF 06 514168003 6118/2020 Co-58 -3.27E-Ol l.21E+OO 3.79E+OO u TF 06 514168003 6/18/2020 Co-60 -2.09E+OO 1.53E+OO 4.21E+OO u TF 06 514168003 6/18/2020 Cr-51 -1.16E+OO 1. lOE+Ol 3.71E+Ol u TF 06 514168003 6118/2020 Cs-134 2.52E+OO l.71E+OO 5.69E+OO u TF 06 514168003 6118/2020 Cs-13 7 -1.26E+OO l.35E+OO 4.0lE+OO u TF 06 514168003 6118/2020 Fe-59 2.lOE+OO 2.75E+OO 9.67E+OO u TF 06 514168003 6118/2020 1-131 6.00E-01 1.97E+OO 6.08E+OO u TF 06 514168003 6/18/2020 K-40 1.13E+03 9.08E+Ol 4.68E+Ol TF 06 514168003 6/18/2020 La-140 -1.57E+OO l.78E+OO 4.08E+OO u TF 06 514168003 6118/2020 Mn-54 1.56E+OO 1.45E+OO 4.86E+OO u TF 06 514168003 6118/2020 Nb-95 2.33E+OO 1.45E+OO 4.84E+OO u TF 06 514168003 6/18/2020 Ru- I 03 4.31E+OO 2.09E+OO 4.77E+OO u TF 06 514168003 6/18/2020 Ru- I 06 -2.13E+Ol 1.23E+Ol 3.23E+Ol u TF 06 514168003 6118/2020 Sb-124 -9.24E-01 3.lOE+OO 9.83E+OO u TF 06 514168003 6118/2020 Sb-125 -1.05E+OO 3.29E+OO l.08E+Ol u TF 06 514168003 6/18/2020 Se-75 -1.61E+OO 2.00E+OO 5.59E+OO u TF 06 514168003 6/18/2020 Th-228 4.26E+OO 3.68E+OO 9.12E+OO u TF 06 514168003 6/i 8/2020 Zn-65 7.39E-01 3.30E+OO l.13E+Ol u TF 06 514168003 6/18/2020 Zr-95 1.15E-Ol 2.35E+OO 7.63E+OO u TF 06 516040003 7/14/2020 Ac-228 1.12E+Ol 1.04E+OI 3.52E+Ol u TF 06 516040003 7/14/2020 Ag-108m -2.50E+OO l.67E+OO 4.53E+OO u TF 06 516040003 7/14/2020 Ag-l!Om -2.35E+OO 2.99E+OO 8.47E+OO u TF 06 516040003 7/14/2020 Ba-140 1.03E+Ol 8.42E+OO 2.97E+Ol u TF 06 516040003 7 /14/2020 Be-7 2.29E+Ol 1.72E+Ol 5.98E+Ol u TF 06 516040003 7114/2020 Ce-141 l.45E+OO 3.24E+OO l .04E+Ol u TF 06 516040003 7II 4/2020 Ce-144 l.37E+Ol 1.26E+Ol 4.09E+Ol u TF 06 516040003 7/14/2020 Co-57 9.47E-Ol 1.80E+OO 5.42E+OO u 209

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/kg) (pCi/kg) (pCi/kg)

TF 06 516040003 7/14/2020 Co-58 -6.60E-Ol l.72E+OO 5.19E+OO u TF 06 516040003 7/,14/2020 Co-60 -3.98E-Ol 2.14E+OO 6.96E+OO u TF 06 516040003 7/14/2020 Cr-51 l.40E+OO l.56E+Ol 5.32E+Ol u TF 06 516040003 7/14/2020 Cs-134 -4.89E+OO 2.74E+OO 6.25E+OO u TF 06 516040003 7/14/2020 Cs-137 2.84E+OO 2.16E+OO 7.54E+OO u TF 06 516040003 7/14/2020 Fe-59 -1.99E+OO 3.44E+OO l.06E+Ol u TF 06 516040003 7/14/2020 I-131 2.58E+OO 2.98E+OO l.04E+Ol u TF 06 516040003 7/14/2020 K-40 4.94E+02 7.74E+Ol 8.00E+Ol TF 06 516040003 7/14/2020 La-140 9.00E-03 2.50E+OO 8.23E+OO u TF 06 516040003 7/14/2020 Mn-54 2.53E+OO 3.04E+OO 7.94E+OO u TF 06 516040003 7/14/2020 Nb-95 -5.75E-Ol 1.92E+OO 5.96E+OO u TF 06 516040003 7/14/2020 Ru-103 -5.98E-Ol l.88E+OO 6.03E+OO u TF 06 516040003 7/14/2020 Ru-106 -1.98E+Ol l.59E+Ol 4.20E+Ol u TF 06 516040003 7/14/2020 Sb-124 -5.08E+OO 5.IOE+OO 1.32E+Ol u TF 06 516040003 7/14/2020 Sb-125 4.68E+OO 5.0IE+OO l.75E+Ol u TF 06 516040003 7/14/2020 Se-75 5.38E-Ol 2.35E+OO 8.12E+OO u TF 06 516040003 7/14/2020 Th-228 8.27E+OO 7.07E+OO l.30E+Ol u TF 06 516040003 7/14/2020 Zn-65 -1.24E+OO 4.79E+OO l.62E+Ol u TF 06 516040003 7/14/2020 Zr-95 3.39E+OO 3.52E+OO 1.22E+Ol u TF 06 518831003 8/12/2020 Ac-228 6.lOE+OO l.27E+Ol 4.32E+Ol u TF 06 518831003 8/12/2020 Ag-108m -l.26E+OO 2.04E+OO 6.45E+OO u TF 06 518831003 8/12/2020 Ag-llOm l.84E+OO 3.43E+OO 1.21E+Ol u TF 06 518831003 8/12/2020 Ba-140 3.93E+OO l.08E+Ol 3.65E+Ol u TF 06 518831003 8/12/2020 Be-7 l.09E+Ol 2.15E+Ol 7.32E+Ol u TF 06 518831003 8/12/2020 Ce-141 -8.16E-Ol 3.65E+OO l.IOE+Ol u TF 06 518831003 8/12/2020 Ce-144 -1.96E+Ol l.29E+Ol 3.59E+Ol u TF 06 518831003 8/12/2020 Co-57 2.82E-Ol l.59E+OO 5.27E+OO u TF 06 518831003 8/12/2020 Co-58 6.26E+OO 2.75E+OO 8.89E+OO u TF 06 518831003 8/12/2020 Co-60 2.98E+OO 2.82E+OO 1.0IE+Ol u TF 06 518831003 8/12/2020 Cr-51 2.46E+Ol 2.18E+Ol 7.62E+Ol u TF 06 518831003 8/12/2020 Cs-134 -6.89E-Ol 3.20E+OO 9.80E+OO u TF 06 518831003 8/12/2020 Cs-137 l.55E-Ol 2.60E+OO 8.43E+OO u TF 06 518831003 8/12/2020 Fe-59 -7.82E+OO 5.96E+OO l.60E+Ol u TF 06 518831003 8/12/2020 I-131 l.25E+OO 3.72E+OO 1.28E+Ol u TF 06 518831003 8/12/2020 K-40 2.16E+03 l.73E+02 5.98E+Ol TF 06 518831003 8/12/2020 La-140 -1.72E+OO 3.38E+OO 9.62E+OO u TF 06 518831003 8/12/2020 Mn-54 -4.74E+OO 2.65E+OO 6.65E+OO u TF 06 518831003 8/12/2020 Nb-95 -2.04E+OO 2.92E+OO 8.57E+OO u TF 06 518831003 8/12/2020 Ru-103 O.OOE+OO O.OOE+OO 5.90E+OO u TF 06 518831003 8/12/2020 Ru- I 06 5.09E+Ol 2.46E+Ol 5.27E+Ol u TF 06 518831003 8/12/2020 Sb-124 -1.20E+OO 4.78E+OO l.54E+Ol u TF 06 518831003 8/12/2020 Sb-125 l.16E+OO 6.08E+OO 2.06E+Ol u TF 06 518831003 8/12/2020 Se-75 -5.70E-Ol 3.30E+OO l.02E+Ol u TF 06 518831003 8/12/2020 Th-228 -3.64E+OO 5.09E+OO 1.53E+Ol u TF 06 518831003 8/12/2020 Zn-65 -2.08E+OO 7.19E+OO 2.32E+Ol u TF 06 518831003 8/12/2020 Zr-95 l.50E-02 4.lOE+OO l.31E+Ol u 210

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/kg) (pCi/kg) (pCi/kg)

TG 08 511871001 5/20/2020 Ac-228 4.07E+Ol 2.81E+Ol 5.69E+Ol u TG 08 511871001 5/20/2020 Ag-108m 2.56E+OO 2.23E+OO 7.17E+OO u TG 08 511871001 5/20/2020 Ag-llOm -3.47E+OO 3.91E+OO l.23E+Ol u TG 08 511871001 5/20/2020 Ba-140 l.55E+Ol l.31E+Ol 4.35E+Ol u TG 08 511871001 5/20/2020 Be-7 2.38E+02 4.54E+Ol 7.54E+Ol TG 08 511871001 5/20/2020 Ce-141 -5.63E+OO 3.77E+OO 1.16E+Ol u TG 08 511871001 5/20/2020 Ce-144 7.45E+OO l.37E+Ol 4.75E+Ol u TG 08 511871001 5/20/2020 Co-57 -4.82E+OO 2.16E+OO 5.15E+OO u TG 08 511871001 5/20/2020 Co-58 2.llE+OO 2.90E+OO l.OIE+Ol u TG 08 511871001 5/20/2020 Co-60 -l.47E+OO 3.13E+OO 9.85E+OO u TG 08 511871001 5/20/2020 Cr-51 -2.44E+Ol 2.llE+Ol 6.40E+Ol u TG 08 511871001 5/20/2020 Cs-134 -l.49E+OO 2.86E+OO 9.36E+OO u TG 08 511871001 5/20/2020 Cs-137 4.86E+OO 3.14E+OO l.02E+Ol u TG 08 511871001 5/20/2020 Fe-59 2.53E+OO 6.15E+OO 2.09E+Ol u TG 08 511871001 5/20/2020 1-131 2.19E+OO 4.03E+OO l.35E+Ol u TG 08 511871001 5/20/2020 K-40 4.21E+03 2.36E+02 7.60E+Ol TG 08 511871001 5/20/2020 La-140 -5.53E+OO 3.84E+OO 9.33E+OO u TG 08 511871001 5/20/2020 Mn-54 -3.38E+OO 2.70E+OO 8.08E+OO u TG 08 511871001 5/20/2020 Nb-95 -2.76E+OO 3.15E+OO 9.22E+OO u TG 08 511871001 5/20/2020 Ru-103 -2.84E+OO 2.80E+OO 8.38E+OO u TG 08 511871001 5/20/2020 Ru-106 l.18E+Ol 2.32E+Ol 7.62E+Ol u TG 08 511871001 5/20/2020 Sb-124 l.14E+OO 6.05E+OO l.99E+Ol u TG 08 511871001 5/20/2020 Sb-125 4.05E+OO 6.40E+OO 2.14E+Ol u TG 08 511871001 5/20/2020 Se-75 l.47E+OO 2.75E+OO 9.35E+OO u TG 08 511871001 5/20/2020 Th-228 9.37E+OO 6.98E+OO l.69E+Ol u TG 08 511871001 5/20/2020 Zn-65 7.48E+OO 6.58E+OO 2.26E+Ol u TG 08 511871001 5/20/2020 Zr-95 -l.12E+OO 5.34E+OO l.67E+Ol u TG 08 514168004 6/17/2020 Ac-228 5.96E+Ol 5.43E+Ol l.66E+02 u TG 08 514168004 6/17/2020 Ag-108m l.16E+Ol 7.99E+OO 2.65E+Ol u TG 08 514168004 6/17/2020 Ag-llOm -2.37E+Ol l.42E+Ol 3.74E+Ol u TG 08 514168004 6/17/2020 Ba-140 2.86E+Ol 4.54E+Ol 1.49E+02 u TG 08 514168004 6/17/2020 Be-7 7.81E+02 1.47E+02 2.14E+02 TG 08 514168004 6/17/2020 Ce-141 -6.07E+OO l.04E+Ol 3.48E+Ol u TG 08 514168004 6/17/2020 Ce-144 3.79E+Ol 3.90E+Ol l.24E+02 u TG 08 514168004 6/17/2020 Co-57 -7.78E+OO 5.66E+OO l.57E+Ol u TG 08 514168004 6/17/2020 Co-58 l.91E+OO 9.65E+OO 3.26E+Ol u TG 08 514168004 6/17/2020 Co-60 2.67E+Ol l.61E+Ol 4.0IE+Ol u TG 08 514168004 6/17/2020 Cr-51 -3.78E+Ol 7.41E+Ol 2.38E+02 u TG 08 514168004 6/17/2020 Cs-134 6.77E+OO 9.88E+OO 3.43E+Ol u TG 08 514168004 6/17/2020 Cs-137 -2.3 IE-Ol 1.IOE+Ol 3.28E+Ol u TG 08 514168004 6/17/2020 Fe-59 6.76E+OO l.97E+Ol 6.62E+Ol u TG 08 514168004 6/17/2020 1-131 -6.24E+OO l.29E+Ol 4.lOE+Ol u TG 08 514168004 6/17/2020 K-40 3.47E+03 3.88E+02 2.97E+02 TG 08 514168004 6/17/2020 La-140 -1.71E+Ol l.19E+Ol 2.85E+Ol u TG 08 514168004 6/17/2020 Mn-54 2.68E+OO 9.54E+OO 3.24E+Ol u TG 08 514168004 6/17/2020 Nb-95 4.85E+OO 9.83E+OO 3.38E+Ol u TG 08 514168004 6/17/2020 Ru-103 -1.1 IE+Ol 9.20E+OO 2.20E+Ol u TG 08 514168004 6/17/2020 Ru-106 l.92E+02 9.53E+Ol 3.19E+02 u TG 08 514168004 6/17/2020 Sb-124 -2.27E+Ol 2.13E+Ol 5.87E+Ol u TG 08 514168004 6/17/2020 Sb-125 -l.96E+Ol 2.33E+Ol 7.04E+Ol u 211

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/kg) (pCi/kg) (pCi/kg)

TG 08 514168004 6/17/2020 Se-75 7.13E+OO 9.23E+OO 3.14E+Ol u TG 08 514168004 6/17/2020 Th-228 -2.08E+Ol l.97E+Ol 5.46E+Ol u TG 08 514168004 6/17/2020 Zn-65 -9.94E+OO 2.40E+Ol 7.55E+Ol u TG 08 514168004 6/1712020 Zr-95 -5.98E+OO l.79E+Ol 5.86E+Ol u TG 08 516040004 7/14/2020 Ac-228 2.59E+Ol 4.28E+Ol 9.53E+Ol u TG 08 516040004 7/14/2020 Ag-108m -1.00E+Ol 5.50E+OO 1.47E+Ol u TG 08 516040004 7/14/2020 Ag-11 Om l.29E+Ol 8.30E+OO 2.88E+Ol u TG 08 516040004 7/14/2020 Ba-140 3.69E+OO 2.57E+Ol 8.44E+Ol u TG 08 516040004 7/14/2020 Be-7 7.41E+02 l.08E+02 1.85E+02 TG 08 516040004 7/14/2020 Ce-141 -3.36E+Ol l.39E+Ol 2.79E+Ol u TG 08 516040004 7/14/2020 Ce-144 l.33E+Ol 3.45E+Ol l.12E+02 u TG 08 516040004 7/14/2020 Co-57 3.56E+OO 4.37E+OO 1.42E+Ol u TG 08 516040004 7/14/2020 Co-58 -1.29E+Ol 6.73E+OO 1.55E+Ol u TG 08 516040004 7/14/2020 Co-60 -l.28E+Ol 6.79E+OO l.51E+Ol u TG 08 516040004 7/14/2020 Cr-51 3.06E+Ol 5.18E+Ol 1.77E+02 u TG 08 516040004 7/14/2020 Cs-134 8.85E+OO 6.41E+OO 2.14E+Ol u TG 08 516040004 7/14/2020 Cs-137 -6.76E+OO 6.35E+OO 1.82E+Ol u TG 08 516040004 7/14/2020 Fe-59 l.87E+Ol l.22E+Ol 4.24E+Ol u TG 08 516040004 7/14/2020 1-131 -3.73E+OO 9.84E+OO 3.23E+Ol u TG 08 516040004 7/14/2020 K-40 3.08E+03 2.92E+02 2.05E+02 TG 08 516040004 7/14/2020 La-140 -l.53E+Ol 9.02E+OO 1.90E+Ol u TG 08 516040004 7/14/2020 Mn-54 2.57E+OO 5.79E+OO 2.00E+Ol u TG 08 516040004 7/14/2020 Nb-95 l.17E+OO 6.27E+OO 2.0lE+Ol u TG 08 516040004 7/14/2020 Ru- I 03 2.92E+OO 6.29E+OO 2.IOE+Ol u TG 08 516040004 7/14/2020 Ru-106 l.31E+Ol 5.56E+Ol 1.82E+02 u TG 08 516040004 7114/2020 Sb-124 -2.34E+Ol l.51E+Ol 3.85E+Ol u TG 08 516040004 7/14/2020 Sb-125 7.52E+OO l.44E+Ol 4.88E+Ol u TG 08 516040004 7/14/2020 Se-75 6.84E+OO 7.29E+OO 2.51E+Ol u TG 08 516040004 7/14/2020 Th-228 O.OOE+OO 2.43E+Ol 4.23E+Ol u TG 08 516040004 7/14/2020 Zn-65 5.51E-Ol l.34E+Ol 3.92E+Ol u TG 08 516040004 7/14/2020 Zr-95 -l.18E+Ol l.17E+Ol 3.33E+Ol u TG 08 518831004 8/12/2020 Ac-228 7.55E+Ol 5.84E+Ol 1.28E+02 u TG 08 518831004 8/12/2020 Ag-108m -5.74E+OO 7.36E+OO 2.30E+Ol u TG 08 518831004 8/12/2020 Ag-llOm -5.12E+OO l.12E+Ol 3.63E+Ol u TG 08 518831004 8/12/2020 Ba-140 6.88E+OO 3.42E+Ol l.15E+02 u TG 08 518831004 8/12/2020 Be-7 9.90E+02 l.65E+02 1.89E+02 TG 08 518831004 8/12/2020 Ce-141 -1.87E+Ol l.37E+Ol 3.78E+Ol u TG 08 518831004 8/12/2020 Ce-144 2.94E+Ol 4.13E+Ol l.38E+02 u TG 08 518831004 8/12/2020 Co-57 7.07E+OO 5.68E+OO 1.89E+Ol u TG 08 518831004 8/12/2020 Co-58 -2.72E+OO 8.90E+OO 2.74E+Ol u TG 08 518831004 8/12/2020 Co-60 -6.78E+OO 8.62E+OO 2.48E+Ol u TG 08 518831004 8/12/2020 Cr-51 8.47E+OO 5.93E+Ol 2.04E+02 u TG 08 518831004 8/12/2020 Cs-134 2.34E+Ol l.09E+Ol 3.68E+Ol u TG 08 518831004 8/12/2020 Cs-137 2.14E+Ol l.80E+Ol 2.51E+Ol u TG 08 518831004 8/12/2020 Fe-59 5.31E+OO l.86E+Ol 6.05E+Ol u TG 08 518831004 8/12/2020 1-131 -4.40E+OO l.IOE+Ol 3.60E+Ol u TG 08 518831004 8/12/2020 K-40 5.29E+03 4.38E+02 2.94E+02 TG 08 518831004 8/12/2020 La-140 -4.12E+OO l.03E+Ol 3.03E+Ol u TG 08 518831004 8/12/2020 Mn-54 2.87E+OO 9.25E+OO 2.95E+Ol u 212

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/kg) (pCi/kg) (pCi/kg)

TG 08 518831004 8/12/2020 Nb-95 -5.03E+OO 8.80E+OO 2.64E+Ol u TG 08 518831004 8/12/2020 Ru-I 03 l.98E-01 8.36E+OO 2.77E+Ol u TG 08 518831004 8/12/2020 Ru- I 06 -4.25E+Ol 7.43E+Ol 2.28E+02 u TG 08 518831004 8/12/2020 Sb-124 2.74E+OO 2.0IE+Ol 6.60E+Ol u TG 08 518831004 8/12/2020 Sb-125 -9.04E+OO 2.llE+Ol 6.82E+Ol u TG 08 518831004 8/12/2020 Se-75 3.49E+OO 9.19E+OO 2.93E+Ol u TG 08 518831004 8112/2020 th-228 4.87E+Ol 3.17E+Ol 5.94E+Ol u TG 08 518831004 8/12/2020 Zn-65 5.07E+Ol 2.00E+Ol 5.28E+Ol u TG 08 518831004 8/12/2020 Zr-95 8.43E+OO l.73E+Ol 5.73E+Ol u TG 08 521446001 9/9/2020 Ac-228 -l.57E+Ol 2.1 IE+Ol 5.68E+Ol u TG 08 521446001 9/9/2020 Ag-108m l.56E+OO 3.24E+OO l.02E+Ol u TG 08 521446001 9/9/2020 Ag-llOm -7.06E+OO 5.43E+OO l.45E+Ol u TG 08 521446001 9/9/2020 Ba-140 -l.73E+Ol 2.03E+Ol 6.30E+Ol u TG 08 521446001 9/9/2020 Be-7 1.31E+03 l.10E+02 l.10E+02 TG 08 521446001 9/9/2020 Ce-141 3.llE+OO l.14E+Ol l.63E+Ol u TG 08 521446001 9/9/2020 Ce-144 -4.22E+Ol 2.31E+Ol 6.32E+Ol u TG 08 521446001 9/9/2020 Co-57 4.32E+OO 2.81E+OO 9.20E+OO u TG 08 521446001 9/9/2020 Co-58 2.32£-01 4.35E+OO 1.42E+Ol u TG 08 521446001 9/9/2020 Co-60 l.02E+Ol 4.90E+OO l.73E+Ol u TG 08 521446001 9/9/2020 Cr-51 -2.84E+Ol 3.66E+Ol l.07E+02 u TG 08 521446001 9/9/2020 Cs-134 2.72E+OO 4.97E+OO l.67E+Ol u TG 08 521446001 9/9/2020 Cs-137 8.71£-01 4.98E+OO 1.66E+Ol u TG 08 521446001 9/9/2020 Fe-59 6.05£-01 9.43E+OO 3.00E+OI u TG 08 521446001 9/9/2020 I-131 5.08E+OO 6.24E+OO 2.19E+Ol u TG 08 521446001 9/9/2020 K-40 2.11E+03 2.04E+02 1.13E+02 TG 08 521446001 9/9/2020 La-140 2.84E+OO 5.81E+OO 2.03E+Ol u TG 08 521446001 9/9/2020 Mn-54 -5.37£-01 3.87E+OO 1.24E+Ol u TG 08 521446001 9/9/2020 Nb-95 1.91E+OO 4.76E+OO 1.59E+Ol u TG 08 521446001 9/9/2020 Ru-103 3.18E+OO 4.IOE+OO l.41E+Ol u TG 08 521446001 9/9/2020 Ru-106 4.32E+Ol 4.43E+Ol 8.87E+Ol u TG 08 521446001 9/9/2020 Sb-124 -4.45E+OO l.18E+Ol 3.72E+Ol u TG 08 521446001 9/9/2020 Sb-125 l.81E+OO 8.88E+OO 2.76E+Ol u TG 08 521446001 9/9/2020 Se-75 -3.93E+OO 5.88E+OO 1.65E+Ol u TG 08 521446001 9/9/2020 Th-228 -9.77E+OO l.13E+Ol 4.00E+Ol u TG 08 521446001 9/9/2020 Zn-65 l.73E+Ol l.06E+OI 3.47E+Ol u TG 08 521446001 9/9/2020 Zr-95 -8.14E+OO 7.58E+OO 2.18E+Ol u TG 08 523906001 1017/2020 Ac-228 1.32E+Ol 5.83E+Ol 7.94E+Ol u TG 08 523906001 1017/2020 Ag-108m -6.25£-02 5.27E+OO 1.76E+Ol u TG 08 523906001 1017/2020 Ag-1 IOm l.15E+Ol l.OOE+Ol 3.48E+Ol u TG 08 523906001 1017/2020 Ba-140 3.44E+Ol 2.89E+Ol 9.73E+Ol u TG 08 523906001 1017/2020 Be-7 6.95E+02 l.07E+02 1.73E+02 TG 08 523906001 1017/2020 Ce-141 -3.97E+Ol 1.30E+Ol 2.51E+Ol u TG 08 523906001 1017/2020 Ce-144 -3.20£-01 3.15E+OI l.03E+02 u TG 08 523906001 1017/2020 Co-57 2.39£-01 4.27E+OO 1.40E+Ol u TG 08 523906001 1017/2020 Co-58 3.83E+OO 5.89E+OO 1.95E+Ol u TG 08 523906001 1017/2020 Co-60 5.18£-01 6.60E+OO 2.18E+Ol u TG 08 523906001 1017/2020 Cr-51 2.77E+Ol 5.43E+Ol 1.87E+02 u TG 08 523906001 1017/2020 Cs-134 -3.63E+OO 8.47E+OO 2.23E+Ol u TG 08 523906001 1017/2020 Cs-137 O.OOE+OO l.86E+Ol 2.14E+Ol u 213

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/kg) (pCi/kg) (pCi/kg)

TG 08 523906001 1017/2020 Fe-59 2.76E+OO l.36E+Ol 4.59E+Ol u TG 08 523906001 1017/2020 1-131 -l.21E+Ol 8.55E+OO 2.55E+Ol u TG 08 523906001 1017/2020 K-40 4.13E+03 3.57E+02 2.20E+02 TG 08 523906001 1017/2020 La-I40 -5.09E+OO 7.52E+OO 2.16E+Ol u TG 08 523906001 1017/2020 Mn-54 9.89E+OO 7.25E+OO l.76E+Ol u TG 08 523906001 1017/2020 Nb-95 8.30E+OO 7.lOE+OO 2.35E+Ol u TG 08 523906001 1017/2020 Ru- I 03 5.93E+OO 6.33E+OO 2.14E+Ol u TG 08 523906001 1017/2020 Ru- I 06 8.33E+OO 5.92E+Ol l.94E+02 u TG 08 523906001 1017/2020 Sb- I24 -2.02E+OO l.15E+Ol 3.58E+Ol u TG 08 523906001 1017/2020 Sb- I25 6.64E+OO 1.65E+Ol 5.61E+Ol u TG 08 523906001 1017/2020 Se-75 l.57E+Ol 8.98E+OO 2.60E+Ol u TG 08 523906001 1017/2020 Th-228 7.89E+Ol 2.17E+Ol 2.80E+Ol TG 08 523906001 1017/2020 Zn-65 6.80E+OO l.65E+Ol 5.00E+Ol u TG 08 523906001 1017/2020 Zr-95 2.54E+Ol l.25E+Ol 4.06E+Ol u TG 09 511871002 5/20/2020 Ac-228 l.60E+Ol l.99E+Ol 4.37E+Ol u TG 09 511871002 5/20/2020 Ag-108m -9.46E-01 l.91E+OO 6.12E+OO u TG 09 511871002 5/20/2020 Ag- I I Om l.95E+OO 4.42E+OO 1.29E+Ol u TG 09 511871002 5/20/2020 Ba-I40 -8.36E+OO l.22E+Ol 3.78E+Ol u TG 09 511871002 5/20/2020 Be- 7 l.59E+02 4.67E+Ol 6.55E+Ol TG 09 511871002 5/20/2020 Ce-I4I -3.28E+OO 3.89E+OO l.lOE+Ol u TG 09 511871002 5/20/2020 Ce-I44 -6.65E+OO l.32E+Ol 4.08E+Ol u TG 09 511871002 5/20/2020 Co-57 -l.14E-01 l.55E+OO 4.95E+OO u TG 09 511871002 5/20/2020 Co-58 -2.53E+OO 3.02E+OO 7.89E+OO u TG 09 511871002 5/20/2020 Co-60 4.19E+OO 3.15E+OO 9.19E+OO u TG 09 511871002 5/20/2020 Cr-51 -3.36E+Ol 2.03E+Ol 5.86E+Ol u TG 09 511871002 5/20/2020 Cs-134 -7.72E-01 2.50E+OO 8.35E+OO u TG 09 511871002 5/20/2020 Cs-137 -l.98E-01 2.52E+OO 8.06E+OO u TG 09 511871002 5/20/2020 Fe-59 2.23E+OO 5.12E+OO l.74E+Ol u TG 09 511871002 5/20/2020 1-131 2.93E+OO 3.76E+OO l.27E+Ol u TG 09 511871002 5/20/2020 K-40 4.17E+03 2.33E+02 8.47E+Ol TG 09 511871002 5/20/2020 La-I40 -5.40E+OO 3.96E+OO l.02E+Ol u TG 09 511871002 5/20/2020 Mn-54 2.86E+OO 2.56E+OO 8.04E+OO u TG 09 511871002 5/20/2020 Nb-95 -l.70E+OO 3.0lE+OO 8.21E+OO u TG 09 511871002 5/20/2020 Ru-103 -4.49E-02 2.23E+OO 7.28E+OO u TG 09 511871002 5/20/2020 Ru-I06 4.09E+Ol 2.53E+Ol 8.15E+Ol u TG 09 511871002 5/20/2020 Sb-124 3.30E+OO 5.05E+OO l.72E+Ol u TG 09 511871002 5/20/2020 Sb-125 -3.74E+OO 5.29E+OO l.66E+Ol u TG 09 511871002 5/20/2020 Se-75 2.39E+OO 2.56E+OO 8.78E+OO u TG 09 511871002 5/20/2020 Th-228 2.56E+OO 5.90E+OO l.41E+Ol u TG 09 511871002 5/20/2020 Zn-65 -7.68E+OO 7.09E+OO 2.15E+Ol u TG 09 511871002 5/20/2020 Zr-95 -2.16E+OO 4.05E+OO l.23E+Ol u TG 09 514168005 6/17/2020 Ac-228 4.63E+Ol 6.70E+Ol 9.49E+Ol u TG 09 514168005 6/17/2020 Ag-108m -4.67E+OO 6.38E+OO l.99E+Ol u TG 09 514168005 6/17/2020 Ag-11 Om -1.38E+Ol 1.30E+Ol 2.58E+Ol u TG 09 514168005 6/17/2020 Ba-I40 -5.89E+OO 3.45E+Ol l.12E+02 u TG 09 514168005 6/17/2020 Be-7 4.24E+02 l.42E+02 2.01E+02 TG 09 514168005 6/17/2020 Ce-I4I -6.08E+Ol l.99E+Ol 3.66E+Ol u TG 09 514168005 6117/2020 Ce-144 3.52E+Ol 4.66E+Ol l.59E+02 u TG 09 514168005 6/17/2020 Co-57 l.77E+OO 5.91E+OO 2.02E+Ol u 214

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/kg) (pCi/kg) (pCi/kg)

TG 09 514168005 6/17/2020 Co-58 -6.98E-01 7.09E+OO 2.28E+Ol u TG 09 514168005 6/17/2020 Co-60 1.16E+Ol 2.06E+Ol 3.25E+Ol u TG 09 514168005 6/17/2020 Cr-51 4.12E+Ol 7.20E+Ol 2.43E+02 u TG 09 514168005 6/17/2020 Cs-134 -9.44E+OO 8.86E+OO 2.54E+Ol u TG 09 514168005 6/17/2020 Cs-137 9.80E+OO 9.42E+OO 2.90E+Ol u TG 09 514168005 6/17/2020 Fe-59 2.06E+OO 1.63E+Ol 5.28E+Ol u TG 09 514168005 6/17/2020 1-131 -3.17E+OO 1.25E+Ol 4.llE+Ol u TG 09 514168005 6/17/2020 K-40 3.98E+03 4.17E+02 2.45E+02 TG 09 514168005 6/17/2020 La-140 2.20E+OO 1.06E+Ol 3.65E+Ol u TG 09 514168005 6/17/2020 Mn-54 8.57E-02 8.20E+OO 2.65E+Ol u TG 09 514168005 6/17/2020 Nb-95 9.lOE+OO 9.77E+OO 3.26E+Ol u TG 09 514168005 6/17/2020 Ru-103 -4.23E+OO 7.53E+OO 2.38E+Ol u TG 09 514168005 6/17/2020 Ru-106 -4.68E+Ol 6.93E+Ol 2.14E+02 u TG 09 514168005 6/17/2020 Sb-124 4.66E+OO 1.62E+Ol 5.64E+Ol u TG 09 514168005 6/17/2020 Sb-125 4.87E+Ol 2.44E+Ol 7.86E+Ol u TG 09 514168005 6/17/2020 Se-75 -2.28E+OO 9.81E+OO 3.25E+Ol u TG 09 514168005 6/17/2020 Th-228 -1.04E+Ol 1.78E+Ol 5.59E+Ol u TG 09 514168005 6/17/2020 Zn-65 -2.81E+OO 2.07E+Ol 5.80E+Ol u TG 09 514168005 6/17/2020 Zr-95 5.02E-01 1.35E+Ol 4.39E+Ol u TG 09 516040005 7/14/2020 Ac-228 1.01E+02 5.41E+Ol 1.23E+02 u TG 09 516040005 7/14/2020 Ag-108m -2.64E-01 7.89E+OO 2.20E+Ol u TG 09 516040005 7/14/2020 Ag-l!Om 1.45E+Ol 8.85E+OO 3.04E+Ol u TG 09 516040005 7/14/2020 Ba-140 -6.16E+OO 3.22E+Ol 1.04E+02 u TG 09 516040005 7/14/2020 Be-7 5.41E+02 1.06E+02 2.05E+02 TG 09 516040005 7/14/2020 Ce-141 2.28E+OO 1.02E+Ol 3.22E+Ol u TG 09 516040005 7/14/2020 Ce-144 -2.26E+Ol 3.84E+Ol l.18E+02 u TG 09 516040005 7/14/2020 Co-57 5.56E+OO 4.88E+OO 1.55E+Ol u TG 09 516040005 7/14/2020 Co-58 -9.31E-01 6.76E+OO 2.28E+Ol u TG 09 516040005 7/14/2020 Co-60 8.97E-01 7.07E+OO 2.34E+Ol u TG 09 516040005 7/14/2020 Cr-51 -8.70E+Ol 6.48E+Ol 1.70E+02 u TG 09 516040005 7/14/2020 Cs-134 -4.lOE+OO 6.68E+OO 2.17E+Ol u TG 09 516040005 7/14/2020 Cs-137 -7.95E-01 6.72E+OO 2.14E+Ol u TG 09 516040005 7/14/2020 Fe-59 -8.33E+OO 1.37E+Ol 3.69E+Ol u TG 09 516040005 7/14/2020 1-131 1.03E+Ol 1.04E+Ol 3.51E+Ol u TG 09 516040005 7/14/2020 K-40 3.76E+03 3.34E+02 1.70E+02 TG 09 516040005 7/14/2020 La-140 8.88E+OO 8.29E+OO 2.93E+Ol u TG 09 516040005 7/14/2020 Mn-54 5.61E+OO 6.90E+OO 2.39E+Ol u TG 09 516040005 7/14/2020 Nb-95 2.86E+OO 8.78E+OO 2.53E+Ol u TG 09 516040005 7/14/2020 Ru-103 4.31E+OO 6.70E+OO 2.14E+Ol u TG 09 516040005 7/14/2020 Ru-106 -9.30E+OO 5.67E+Ol 1.8IE+02 u TG 09 516040005 7/14/2020 Sb-124 -1.49E+OO 1.lOE+Ol 3.47E+Ol u TG 09 516040005 7114/2020 Sb-125 2.24E+Ol 2.74E+Ol 5.46E+Ol u TG 09 516040005 7/14/2020 Se-75 -2.18E+OO 7.27E+OO 2.43E+OI u TG 09 516040005 7/14/2020 Th-228 O.OOE+OO 3.07E+Ol 3.98E+Ol u TG 09 516040005 7114/2020 Zn-65 6.88E+OO l.38E+Ol 4.72E+Ol u TG 09 516040005 7/14/2020 Zr-95 -1.73E+Ol 1.49E+Ol 3.62E+Ol u TG 09 518831005 8/12/2020 Ac-228 7.49E+Ol 5.59E+Ol 1.50E+02 u TG 09 518831005 8/12/2020 Ag-108m -4.72E+OO 7.64E+OO 2.31E+Ol u TG 09 518831005 8/12/2020 Ag-l!Om -1.22E+Ol 1.22E+Ol 3.60E+Ol u 215

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/kg) (pCi/kg) (pCi/kg)

TG 09 518831005 8/12/2020 Ba-140 -6.12E+Ol 4.31E+Ol l.OOE+02 u TG 09 518831005 8/12/2020 Be-7 9.61E+02 l.63E+02 2.13E+02 TG 09 518831005 8/12/2020 Ce-141 9.75E+OO l.27E+Ol 4.25E+Ol u TG 09 518831005 8/12/2020 Ce-144 -l.24E+02 5.47E+Ol l.33E+02 u TG 09 518831005 8/12/2020 Co-57 l.43E+Ol l.15E+Ol l.88E+Ol u TG 09 518831005 8/12/2020 Co-58 l.97E+OO 8.05E+OO 2.76E+Ol u TG 09 . 518831005 8/12/2020 Co-60 -6.54E+OO 8.54E+OO 2.47E+Ol u TG 09 518831005 8/12/2020 Cr-51 -2.51E+Ol 6.84E+Ol 2.15E+02 u TG 09 518831005 8/12/2020 Cs-134 -l.31E+Ol l.08E+Ol 2.57E+Ol u TG 09 518831005 8/12/2020 Cs-137 l.OIE+Ol 8.21E+OO 2.92E+Ol u TG 09 518831005 8/12/2020 Fe-59 2.63E+Ol l.83E+Ol 6.14E+Ol u TG 09 518831005 8/12/2020 1-131 l.03E+Ol l.42E+Ol 4.72E+Ol u TG 09 518831005 8/12/2020 K-40 5.43E+03 4.28E+02 2.05E+02 TG 09 518831005 8/12/2020 La-140 5.13E+OO l.28E+Ol 4.38E+Ol u TG 09 518831005 8/12/2020 Mn-54 -1.73E-Ol 9.05E+OO 3.03E+Ol u TG 09 518831005 8/12/2020 Nb-95 8.44E+OO 9.91E+OO 3.12E+Ol u TG 09 518831005 8/12/2020 Ru-103 l.64E+Ol l.18E+Ol 2.18E+Ol u TG 09 518831005 8/12/2020 Ru-106 -l.65E+Ol 7.99E+Ol 2.68E+02 u TG 09 518831005 8/12/2020 Sb-124 l.87E+Ol l.66E+Ol 6.27E+Ol u TG 09 518831005 8/12/2020 Sb-125 -4.80E+OO 2.21E+Ol 6.96E+Ol u TG 09 518831005 8/12/2020 Se-75 -l.74E+Ol l.14E+Ol 3.16E+Ol u TG 09 518831005 8/12/2020 Th-228 l.80E+Ol 2.02E+Ol 4.52E+Ol u TG 09 518831005 8/12/2020 Zn-65 -6.24E+OO 2.21E+Ol 7.15E+Ol u TG 09 518831005 8/12/2020 Zr-95 l.72E+Ol l.97E+Ol 6.22E+Ol u TG 09 521446002 9/9/2020 Ac-228 l.IOE+Ol 2.75E+Ol 7.86E+Ol u TG 09 521446002 91912020 Ag-108m 3.28E+OO 4.15E+OO l.26E+Ol u TG 09 521446002 9/9/2020 Ag-1 lOm -3.44E+OO 6.80E+OO 2.22E+Ol u TG 09 521446002 91912020 Ba-140 9.88E+OO 2.19E+Ol 7.26E+Ol u TG 09 521446002 9/9/2020 Be-7 l.43E+03 l.20E+02 l.14E+02 TG 09 521446002 91912020 Ce-141 -7.82E-Ol 7.50E+OO 2.13E+Ol u TG 09 521446002 9/9/2020 Ce-144 9.35E-Ol 2.40E+Ol 7.50E+Ol u TG 09 521446002 91912020 Co-57 l.80E+OO 3.34E+OO l.06E+Ol u TG 09 521446002 91912020 Co-58 -l.52E+OO 4.93E+OO l.52E+Ol u TG 09 521446002 9/9/2020 Co-60 l.13E+Ol 6.23E+OO l.99E+Ol u TG 09 521446002 91912020 Cr-51 l.89E+Ol 3.98E+Ol l.35E+02 u TG 09 521446002 9/9/2020 Cs-134 5.28E+OO 4.98E+OO l.52E+Ol u TG 09 521446002 9/9/2020 Cs-137 2.24E+OO 4.76E+OO l.57E+Ol u TG 09 521446002 91912020 Fe-59 2.39E+OO 8.48E+OO 2.89E+Ol u TG 09 521446002 91912020 1-131 l.96E+OO 7.29E+OO 2.45E+Ol u TG 09 521446002 91912020 K-40 3.16E+03 2.55E+02 l.37E+02 TG 09 521446002 9/9/2020 La-140 3.16E+OO 7.15E+OO 2.43E+Ol u TG 09 521446002 91912020 Mn-54 2.61E+OO 4.87E+OO l.52E+Ol u TG 09 521446002 91912020 Nb-95 -2.84E+OO 6.47E+OO l.77E+Ol u TG 09 521446002 9/9/2020 Ru-103 5.47E-Ol 4.28E+OO l.41E+Ol u TG 09 521446002 91912020 Ru-106 -5.84E+Ol 4.31E+Ol l.20E+02 u TG 09 521446002 91912020 Sb-124 -5.97E+OO l.27E+Ol 3.89E+Ol u TG 09 521446002 9/9/2020 Sb-125 -1.65E+Ol l.32E+Ol 3.38E+Ol u TG 09 521446002 91912020 Se-75 -l.14E+Ol 1.02E+Ol l.78E+Ol u TG 09 521446002 91912020 Th-228 8.96E+OO 9.68E+OO 2.92E+Ol u TG 09 521446002 91912020 Zn-65 2.37E+Ol l.19E+Ol 3.41E+Ol u 216

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/kg) (pCi/kg) (pCi/kg)

TG 09 521446002 91912020 Zr-95 4.19E+OO 9.67E+OO 2.83E+Ol u TG 09 523906002 10/7/2020 Ac-228 l.71E+02 5.96E+Ol 7.40E+Ol TG 09 523906002 1017/2020 Ag-108m 2.39E+OO 4.31E+OO l.47E+Ol u TG 09 523906002 1017/2020 Ag-11 Om -2.59£-01 7.49E+OO 2.38E+Ol u TG 09 523906002 1017/2020 Ba-140 l.97E+Ol 2.47E+Ol 8.39E+Ol u TG 09 523906002 1017/2020 Be-7 l.05E+03 l.26E+02 l.49E+02 TG 09 523906002 1017/2020 Ce-141 -2.39E+Ol l.14E+Ol 2.34E+Ol u TG 09 523906002 1017/2020 Ce-144 l.30E+OI 2.97E+Ol 9.66E+Ol u TG 09 523906002 1017/2020 Co-57 6.14E+OO 3.97E+OO l.27E+Ol u TG 09 523906002 10/7/2020 Co-58 l.22E+Ol 6.44E+OO 2.13E+Ol u TG 09 523906002 1017/2020 Co-60 l.OOE+OO 5.24E+OO l.78E+Ol u TG 09 523906002 1017/2020 Cr-51 -8.97E+Ol 4.94E+Ol l.39E+02 u TG 09 523906002 1017/2020 Cs-134 -4.80E+OO 8.22E+OO 2.15E+Ol u TG 09 523906002 1017/2020 Cs-137 3.93E+OO 5.95E+OO 2.00E+Ol u TG 09 523906002 1017/2020 Fe-59 5.67E+OO l.35E+Ol 4.51E+Ol u TG 09 523906002 1017/2020 1-131 4.47E+OO 7.98E+OO 2.74E+Ol u TG 09 523906002 1017/2020 K-40 O.OOE+OO 4.08E+02 l.91E+02 u TG 09 523906002 1017/2020 La-140 -l.52E+Ol 9.69E+OO 2.37E+Ol u TG 09 523906002 1017/2020 Mn-54 -3.70E+OO 5.83E+OO l.75E+Ol u TG 09 523906002 10/7/2020 Nb-95 -6.88E+OO 6.58E+OO l.91E+Ol u TG 09 523906002 1017/2020 Ru-103 -l.62E+OO 5.88E+OO l.92E+Ol u TG 09 523906002 1017/2020 Ru-106 -l.41E+02 6.41E+Ol l.51E+02 u TG 09 523906002 1017/2020 Sb-124 -2.68E+OO l.26E+Ol 3.97E+Ol u TG 09 523906002 1017/2020 Sb-125 l.45E+Ol 1.60E+Ol 5.46E+Ol u TG 09 523906002 1017/2020 Se-75 5.56E+OO 6.23E+OO 2.17E+Ol u TG 09 523906002 10/7/2020 Th-228 3.98E+OO 2.0lE+Ol 2.94E+Ol u TG 09 523906002 1017/2020 Zn-65 8.61E+OO 1.40E+Ol 4.39E+Ol u TG 09 523906002 1017/2020 Zr-95 -1.27E+Ol l.08E+Ol 3.03E+Ol u TG 10 511871003 5/20/2020 Ac-228 -6.47E+OO 1.46E+Ol 4.33E+Ol u TG 10 511871003 5/20/2020 Ag-108m -7.43£-01 2.47E+OO 7.05E+OO u TG 10 511871003 5/20/2020 Ag-llOm -3.79E+OO 3.71E+OO l.13E+Ol u TG 10 511871003 5/20/2020 Ba-140 8.65E+OO 1.28E+Ol 4.19E+Ol u TG 10 511871003 5/20/2020 Be-7 3.43E+02 4.llE+Ol 6.06E+Ol TG 10 511871003 5/20/2020 Ce-141 9.lOE+OO 7.27E+OO l.12E+Ol u TG 10 511871003 512012020 Ce-144 -2.29E+Ol l.47E+Ol 4.lOE+Ol u TG 10 511871003 5/20/2020 Co-57 2.64£-01 l.74E+OO 5.59E+OO u TG 10 511871003 5/20/2020 Co-58 4.51E+OO 2.71E+OO 9.llE+OO u TG 10 511871003 5/20/2020 Co-60 -5.36£-01 2.88E+OO 9.61E+OO u TG 10 511871003 5/20/2020 Cr-51 l.67E+Ol 2.19E+Ol 7.37E+Ol u TG 10 511871003 5/20/2020 Cs-134 -2.51E+OO 2.73E+OO 8.46E+OO u TG 10 511871003 5/20/2020 Cs-137 6.87E+OO 3.65E+OO 8.60E+OO u TG 10 511871003 5/20/2020 Fe-59 2.09E+OO 5.56E+OO l.84E+Ol u TG 10 511871003 5/20/2020 1-131 l.83E+OO 4.04E+OO l.35E+Ol u TG 10 511871003 5/20/2020 K-40 3.67E+03 2.15E+02 8.81E+Ol TG 10 511871003 5/20/2020 La-140 l.lOE+Ol 5.37E+OO l.50E+Ol u TG 10 511871003 5/20/2020 Mn-54 3.40£-01 2.60E+OO 8.73E+OO u TG 10 511871003 5/20/2020 Nb-95 -2.00E+OO 2.72E+OO 8.67E+OO u TG 10 511871003 5/20/2020 Ru-103 -l.03E+OO 3.41E+OO 7.77E+OO u TG 10 511871003 5/20/2020 Ru-106 l.42E+Ol 2.28E+Ol 7.40E+Ol u 217

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/kg) (pCi/kg) (pCi/kg)

TG 10 511871003 5/20/2020 Sb-124 -1.08E+OO 5.62E+OO 1.82E+Ol u TG 10 511871003 5/20/2020 Sb-125 -4.30E+OO 6.48E+OO 2.03E+Ol u TG 10 511871003 5/20/2020 Se-75 2.50E+OO 3.17E+OO 1.08E+Ol u TG 10 511871003 5/20/2020 Th-228 5.02E+OO 7.93E+OO 1.73E+Ol u TG 10 511871003 5/20/2020 Zn-65 -1.40E+Ol 7.55E+OO L86E+or u TG 10 511871003 5/20/2020 Zr-95 -1.08E+OO 4.67E+OO 1.55E+Ol u TG 10 514168006 6/17/2020 Ac-228 1.24E+02 4.33E+Ol 1.29E+02 u TG 10 514168006 6/17/2020 Ag-108m 5.90E-01 6.18E+OO 1.90E+Ol u TG 10 514168006 6/17/2020 Ag-llOm -7.08E+OO 1.21E+Ol 3.35E+Ol u TG 10 514168006 6/17/2020 Ba-140 -9.42E+Ol 4.51E+Ol 9.75E+Ol u TG 10 514168006 6/17/2020 Be-7 5.39E+02 1.15E+02 1.79E+02 TG 10 514168006 6/17/2020 Ce-141 -8.57E-01 1.08E+Ol 3.57E+Ol u TG 10 514168006 6/17/2020 Ce-144 4.34E+OO 3.97E+Ol l.32E+02 u TG 10 514168006 6/17/2020 Co-57 4.68E+OO 5.46E+OO 1.83E+Ol u TG 10 514168006 6/17/2020 Co-58 9.95E+OO 7.64E+OO 2.64E+Ol u TG 10 514168006 6/17/2020 Co-60 -8.39E+OO 8.07E+OO 2.32E+Ol u TG 10 514168006 6/17/2020 Cr-51 -1.72E+Ol 6.13E+Ol 1.96E+02 u TG 10 514168006 6/17/2020 Cs-134 5.91E+OO 7.81E+OO 2.71E+Ol u TG 10 514168006 6/17/2020 Cs-137 1.33E+Ol 9.77E+OO 3.03E+Ol u TG 10 514168006 6/17/2020 Fe-59 5.15E+OO 1.65E+Ol 5.56E+Ol u TG 10 514168006 6/17/2020 1-131 1.94E+OO 1.24E+Ol 4.0lE+Ol u TG 10 514168006 6/17/2020 K-40 5.02E+03 3.81E+02 2.53E+02 TG 10 514168006 6/17/2020 La-140 -3.06E+OO l.27E+Ol 4.04E+Ol u TG 10 514168006 6/17/2020 Mn-54 1.15E+Ol 7.60E+OO 2.61E+Ol u TG 10 514168006 6/17/2020 Nb-95 4.50E+OO 7.18E+OO 2.23E+Ol u TG 10 514168006 6/17/2020 Ru-103 -9.43E+OO 7.91E+OO 2.25E+Ol u TG 10 514168006 6/17/2020 Ru-106 8.56E+Ol 7.08E+Ol 2.23E+02 u TG 10 514168006 6/17/2020 Sb-124 -3.30E+Ol 1.94E+Ol 3.00E+Ol u TG 10 514168006 6/17/2020 Sb-125 8.31E+OO 1.91E+Ol 6.22E+Ol u TG 10 514168006 6/17/2020 Se-75 -2.80E+OO 9.02E+OO 2.89E+Ol u TG 10 514168006 6/17/2020 Th-228 -2.37E+Ol 1.67E+Ol 4.23E+Ol u TG 10 514168006 6/17 /2020 Zn-65 1.0lE+Ol 1.68E+Ol 5.73E+Ol u TG 10 514168006 6/17/2020 Zr-95 3.47E+OO 1.45E+Ol 4.38E+Ol u TG 10 516040006 7/14/2020 Ac-228 3.59E+Ol 3.48E+Ol 8.52E+Ol u TG 10 516040006 7/14/2020 Ag-108m 3.22E+OO 4.21E+OO 1.40E+Ol u TG 10 516040006 7/14/2020 Ag-llOm 8.50E+OO 8.56E+OO 2.06E+Ol u TG 10 516040006 7/14/2020 Ba-140 1.19E+Ol 2.48E+Ol 8.08E+Ol u TG 10 516040006 7/14/2020 Be-7 1.07E+03 1.06E+02 1.41E+02 TG 10 516040006 7/14/2020 Ce-141 -3.81E-01 7.18E+OO 2.27E+Ol u TG 10 516040006 7/14/2020 Ce-144 -2.12E+Ol 2.65E+Ol 8.05E+Ol u TG 10 516040006 7/14/2020 Co-57 3.33E+OO 3.54E+OO 1.14E+Ol u TG 10 516040006 7/14/2020 Co-58 7.86E+OO 4.97E+OO 1.69E+Ol u TG 10 516040006 7/14/2020 Co-60 9.99E+OO l.31E+Ol 1.85E+Ol u TG 10 516040006 7/14/2020 Cr-51 5.90E+Ol 4.29E+Ol 1.42E+02 u TG 10 516040006 7/14/2020 Cs-134 6.71E+OO 7.30E+OO 1.70E+Ol u TG 10 516040006 7/14/2020 Cs-137 2.00E+OO 5.34E+OO 1.83E+Ol u TG 10 516040006 7/14/2020 Fe-59 -2.52E+OO 1.lOE+Ol 3.51E+Ol u TG 10 516040006 7/14/2020 1-131 -5.90E+OO 6.99E+OO 2.18E+Ol u TG 10 516040006 7114/2020 K-40 2.43E+03 2.04E+02 1.53E+02 218

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/kg) (pCi/kg) (pCi/kg)

TG 10 516040006 7/14/2020 La-140 -3.65E-01 7.26E+OO 2.40E+Ol u TG 10 516040006 7/14/2020 Mn-54 -7.69E+OO 4.95E+OO l.38E+Ol u TG 10 516040006 7/14/2020 Nb-95 6.16E+OO 5.07E+OO 1.74E+Ol u TG 10 516040006 7/14/2020 Ru-103 -3.62E+OO 5.68E+OO l.55E+Ol u TG 10 516040006 7/14/2020 Ru-106 5.74E+Ol 4.64E+Ol l.51E+02 u TG 10 516040006 7/14/2020 Sb-124 6.79E+OO l.18E+Ol 4.07E+Ol u TG 10 516040006 7/14/2020 Sb-125 2.96E+OO l.52E+Ol 4.45E+Ol u TG 10 516040006 7/14/2020 Se-75 -5.58E+OO 6.09E+OO 1.95E+Ol u TG 10 516040006 7/14/2020 Th-228 4.56E+OO l.26E+Ol 3.19E+Ol u TG 10 516040006 7/14/2020 Zn-65 -l.16E+Ol l.32E+Ol 3.36E+Ol u TG 10 516040006 7/14/2020 Zr-95 -4.29E+OO 9.89E+OO 2.81E+Ol u TG 10 518831006 8/12/2020 Ac-228 -8.63E+OO 3.48E+Ol 1.13E+02 u TG 10 518831006 8/12/2020 Ag-108m -l.95E+OO 5.92E+OO l.92E+Ol u TG 10 518831006 8/12/2020 Ag-llOm -6.54E-01 l.OOE+Ol 3.17E+Ol u TG 10 518831006 8/12/2020 Ba-140 -2.22E+Ol 2.87E+Ol 8.62E+Ol u TG 10 518831006 8/12/2020 Be-7 4.88E+02 1.26E+02 l.43E+02 TG 10 518831006 8/12/2020 Ce-141 -l.71E+Ol l.17E+Ol 2.86E+Ol u TG 10 518831006 8/12/2020 Ce-144 -4.25E+Ol 4.lOE+Ol l.19E+02 u TG 10 518831006 8/12/2020 Co-57 2.16E-02 4.97E+OO l.58E+Ol u TG 10 518831006 8/12/2020 Co-58 9.52E+OO 6.47E+OO 2.29E+Ol u TG 10 518831006 8/12/2020 Co-60 l.69E+OO 7.70E+OO 2.63E+Ol u TG 10 518831006 8/12/2020 Cr-51 2.llE+Ol 5.45E+Ol l.88E+02 u TG 10 518831006 8/12/2020 Cs-134 4.27E+OO 7.79E+OO 2.39E+Ol u TG 10 518831006 8/12/2020 Cs-137 5.30E-Ol 7.44E+OO 2.27E+Ol u TG 10 518831006 8/12/2020 Fe-59 -l.27E+Ol l.67E+Ol 5.18E+Ol u TG 10 518831006 8/12/2020 I-131 -2.54E+OO 1.00E+Ol 3.31E+Ol u TG 10 518831006 8/12/2020 K-40 5.16E+03 4.17E+02 9.00E+Ol TG 10 518831006 8/12/2020 La-140 -6.57E+OO l.05E+Ol 3.04E+Ol u TG 10 518831006 8/12/2020 Mn-54 -5.28E+OO 8.29E+OO 2.47E+Ol u TG 10 518831006 8/12/2020 Nb-95 -l.18E+OO 6.74E+OO 2.13E+Ol u TG 10 518831006 8/12/2020 Ru-103 2.88E+OO 5.76E+OO l.97E+Ol u TG 10 518831006 8/12/2020 Ru- I 06 -l.53E+Ol 5.87E+Ol l.87E+02 u TG 10 518831006 8/12/2020 Sb-124 7.56E+OO 2.08E+Ol 7.lOE+Ol u TG 10 518831006 8/12/2020 Sb-125 5.07E+OO l.52E+Ol 5.18E+Ol u TG 10 518831006 8/12/2020 Se-75 -l.15E+Ol 8.48E+OO 2.54E+Ol u TG 10 518831006 8/12/2020 Th-228 2.59E+Ol 2.48E+Ol 3.58E+Ol u TG 10 518831006 8/ 12/2020 Zn-65 l.65E+Ol l.51E+Ol 5.08E+Ol u TG 10 518831006 8/12/2020 Zr-95 -9.0lE+OO l.27E+Ol 3.74E+Ol u TG 10 521446003 91912020 Ac-228 9.60E+Ol 4.21E+Ol l.07E+02 u TG 10 521446003 91912020 Ag-108m 3.98E+OO 4.49E+OO l.55E+Ol u TG 10 521446003 91912020 Ag-llOm 6.61E+OO 6.67E+OO 2.28E+Ol u TG 10 521446003 9/9/2020 Ba-140 -2.lOE+Ol 2.82E+Ol 8.88E+Ol u TG 10 521446003 9/9/2020 Be-7 l.11E+03 l.12E+02 l.40E+02 TG 10 521446003 91912020 Ce-141 -8.14E+OO 8.98E+OO 2.76E+Ol u TG 10 521446003 91912020 Ce-144 5.96E+OO 3.31E+Ol l.08E+02 u TG 10 521446003 91912020 Co-57 5.23E+OO 4.29E+OO l.40E+Ol u TG 10 521446003 91912020 Co-58 l.66E+OO 5.37E+OO l.78E+Ol u TG 10 521446003 91912020 Co-60 2.99E+OO 6.52E+OO 2.26E+Ol u TG 10 521446003 9/9/2020 Cr-51 -8.48E+Ol 5.21E+Ol l.55E+02 u 219

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/kg) (pCi/kg) (pCi/kg)

TG 10 521446003 91912020 Cs-134 2.55E+OO 6.65E+OO 2.20E+Ol u TG IO 521446003 91912020 Cs-137 -2.14E+OO 5.71E+OO 1.83E+Ol u TG IO 521446003 9/9/2020 Fe-59 -6.54E+OO 1.23E+Ol 3.66E+Ol u TG IO 521446003 91912020 I-131 -2.03E+Ol l.05E+Ol 2.89E+Ol u TG IO 521446003 91912020 K-40 3.21E+03 3.04E+02 1.87E+02 TG IO 521446003 91912020 La-140 -8.17E+OO 1.03E+Ol 3.08E+Ol u TG IO 521446003 91912020 Mn-54 2.09E+OO 5.27E+OO 1.75E+Ol u TG 10 521446003 91912020 Nb-95 -3.42E+OO 5.64E+OO 1.74E+Ol u TG IO 521446003 91912020 Ru-103 -9.03E+OO 5.40E+OO 1.49E+Ol u TG 10 521446003 9/9/2020 Ru-106 5.28E+Ol 5.32E+Ol 1.40E+02 u TG 10 521446003 91912020 Sb-124 8.76E+OO 9.34E+OO 3.45E+Ol u TG 10 521446003 91912020 Sb-125 1.88E+Ol l.43E+Ol 4.90E+Ol u TG 10 521446003 91912020 Se-75 -3.40E-01 8.48E+OO 2.26E+Ol u TG IO 521446003 91912020 Th-228 7.90E+OO 1.79E+Ol 3.27E+Ol u TG IO 521446003 91912020 Zn-65 -2.27E+Ol 1.46E+Ol 4.lOE+Ol u TG IO 521446003 91912020 Zr-95 6.24E+OO 1.03E+Ol 3.46E+Ol u TG IO 523906003 101712020 Ac-228 1.35E+02 3.99E+Ol 5.76E+Ol TG IO 523906003 101712020 Ag-108m -4.34E+OO 4.31E+OO 1.35E+Ol u TG IO 523906003 101712020 Ag-llOm 6.03E+OO 7.26E+OO 2.22E+Ol u TG IO 523906003 101712020 Ba-140 -8.14E+OO 2.llE+Ol 6.90E+Ol u TG IO 523906003 101712020 Be-7 1.05E+03 1.12E+02 1.32E+02 TG IO 523906003 101712020 Ce-141 -2.0IE+Ol 9.20E+OO 2.33E+Ol u TG IO 523906003 101712020 Ce-144 -2.06E+Ol 3.40E+Ol 9.72E+Ol u TG IO 523906003 101712020 Co-57 2.30E+OO 4.00E+OO 1.30E+Ol u TG IO 523906003 101712020 Co-58 -3.76E+OO 5.77E+OO 1.57E+Ol u TG IO 523906003 101712020 Co-60 -2.87E+OO 6.05E+OO 1.71E+Ol u TG 10 523906003 101712020 Cr-51 -8.63E+OO 4.28E+Ol 1.45E+02 u TG IO 523906003 101712020 Cs-134 -2.69E+OO 6.08E+OO 1.93E+Ol u TG IO 523906003 101712020 Cs-137 -9.30E+OO 7.32E+OO 1.89E+Ol u TG 10 523906003 101712020 Fe-59 -3.16E+OO 9.64E+OO 2.99E+Ol u TG IO 523906003 101712020 I-131 4.25E+OO 7.0lE+OO 2.42E+Ol u TG 10 523906003 101712020 K-40 4.64E+03 3.42E+02 l.56E+02 TG 10 523906003 101712020 La-140 -3.30E+OO 6.72E+OO 2.12E+Ol u TG 10 523906003 101712020 Mn-54 -1.0IE+OO 4.91E+OO 1.58E+Ol u TG IO 523906003 101712020 Nb-95 -2.87E+OO 5.93E+OO 1.88E+Ol u TG 10 523906003 101712020 Ru-103 -5.03E+OO 4.74E+OO 1.46E+Ol u TG 10 523906003 101712020 Ru-106 1.21E+02 7.35E+Ol 1.28E+02 u TG 10 523906003 101712020 Sb-124 -2.08E+Ol 1.16E+Ol 2.69E+Ol u TG 10 523906003 101712020 Sb-125 -2.76E+OO 1.31E+Ol 4.38E+Ol u TG 10 523906003 101712020 Se-75 -1.30E+Ol 7.44E+OO 1.96E+Ol u TG 10 523906003 101712020 Th-228 1.71E+Ol 1.37E+Ol 3.43E+Ol u TG 10 523906003 101712020 Zn-65 1.90E+Ol 1.27E+Ol 3.92E+Ol u TG 10 523906003 101712020 Zr-95 1.23E+Ol 1.29E+Ol 3.13E+Ol u 220

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/L) (pCi/ L) (pCi/ L)

TM 15 501554001 1/15/2020 Ac-228 -5.18E+OO 4.65E+OO 9.07E+OO u TM 15 501554001 1/15/2020 Ag-108m 6.06E-01 5.24E-01 1.68E+OO u TM 15 501554001 1/15/2020 Ag-llOm -8.92E-01 8.59E-01 2.65E+OO u TM 15 501554001 1/15/2020 Ba-140 1.19E+OO 2.63E+OO 8.41E+OO u TM 15 501554001 1/15/2020 Be-7 1.08E+Ol 5.40E+OO 1.63E+Ol u TM 15 501554001 1/15/2020 Bi-214 O.OOE+OO 2.82E+OO 4.73E+OO u TM 15 501554001 1/15/2020 Ce-141 -1.64E+OO 1.04E+OO 3.22E+OO u TM 15 501554001 1/15/2020 Ce-144 2.61E-01 3.56E+OO 1.22E+Ol u TM 15 501554001 1/15/2020 Co-57 l.73E-01 4.90E-01 1.69E+OO u TM 15 501554001 1/15/2020 Co-58 9.25E-01 6.IOE-01 1.99E+OO u TM 15 501554001 1/15/2020 Co-60 2.53E-01 6.70E-Ol 2.28E+OO u TM 15 501554001 1/15/2020 Cr-51 -1.05E+OO 5.05E+OO 1.64E+Ol u TM 15 501554001 1/15/2020 Cs-134 -l.18E+OO l.02E+OO 1.97E+OO u TM 15 501554001 1/15/2020 Cs-137 8.58E+OO 1.17E+OO 1.87E+OO M TM 15 501554001 1/15/2020 Fe-59 1.90E+OO 1.45E+OO 4.68E+OO u TM 15 501554001 1/15/2020 1-131 -5.19E-02 1.46E-01 4.81E-01 u TM 15 501554001 1/15/2020 1-131 6.81E-01 8.96E-Ol 2.92E+OO u TM 15 501554001 1/15/2020 K-40 1.59E+03 9.18E+Ol 1.86E+Ol TM 15 501554001 1/15/2020 La-140 -5.50E-01 8.17E-01 2.59E+OO u TM 15 501554001 1/15/2020 Mn-54 -5.46E-01 5.71E-Ol 1.78E+OO u TM 15 501554001 1/15/2020 Nb-95 8.79E-01 9.62E-Ol 2.07E+OO u TM 15 501554001 1/15/2020 Pb-212 1.80E+OO 2.38E+OO 4.44E+OO u TM 15 501554001 1/15/2020 Pb-214 4.40E+OO 3.21E+OO 4.73E+OO u TM 15 501554001 1/15/2020 Ru-103 -3.31E-01 5.80E-01 1.80E+OO u TM 15 501554001 1/15/2020 Ru-106 -2.05E+OO 4.82E+OO 1.60E+Ol u TM 15 501554001 1/15/2020 Sb-124 -1.59E+OO 1.35E+OO 3.99E+OO u TM 15 501554001 1/15/2020 Sb-125 7.23E-01 1.57E+OO 5.08E+OO u TM 15 501554001 1/15/2020 Se-75 -2.86E-01 7.61E-01 2.49E+OO u TM 15 501554001 1/15/2020 Th-228 1.80E+OO 2.38E+OO 4.44E+OO u TM 15 501554001 1/15/2020 Zn-65 4.39E-01 1.50E+OO 4.89E+OO u TM 15 501554001 1/15/2020 Zr-95 -2.55E-01 9.96E-01 3.29E+OO u TM 15 504490001 2/12/2020 Ac-228 -4.93E+OO 3.83E+OO 7.73E+OO u TM 15 504490001 2/12/2020 Ag-108m -9.24E-03 4.95E-01 1.48E+OO u TM 15 504490001 2/12/2020 Ag-1 !0m 3.04E-01 7.35E-01 2.38E+OO u TM 15 504490001 2/12/2020 Ba-140 -1.0IE-01 2.72E+OO 8.97E+OO u TM 15 504490001 2/12/2020 Be-7 -1.38E+OO 4.59E+OO 1.51E+Ol u TM 15 504490001 2/12/2020 Bi-214 1.26E+OO 3.09E+OO 4.20E+OO u TM 15 504490001 2/12/2020 Ce-141 -1.91E+OO 1.42E+OO 2.98E+OO u TM 15 504490001 2/12/2020 Ce-144 1.18E-01 3.35E+OO 1.07E+Ol u TM 15 504490001 2/12/2020 Co-57 -3.83E-01 6.21E-Ol 1.44E+OO u TM 15 504490001 2/12/2020 Co-58 -3.52E-01 5.75E-01 1.78E+OO u TM 15 504490001 2/12/2020 Co-60 -7.0IE-01 6.27E-01 1.92E+OO u TM 15 504490001 2/12/2020 Cr-51 -3.IOE-02 4.81E+OO 1.63E+Ol u TM 15 504490001 2/12/2020 Cs-134 4.53E-01 5.97E-01 1.95E+OO u TM 15 504490001 2/12/2020 Cs-137 9.69E+OO 1.llE+OO 1.60E+OO M TM 15 504490001 2/12/2020 Fe-59 -1.30E+OO l.38E+OO 4.40E+OO u TM 15 504490001 2/12/2020 1-131 8.60E-02 2.63E-01 8.92E-01 u TM 15 504490001 2/12/2020 1-131 -4.76E-01 1.02E+OO 3.38E+OO u TM 15 504490001 2/12/2020 K-40 1.66E+03 8.99E+Ol 1.63E+Ol TM 15 504490001 2/12/2020 La-140 -9.37E-01 6.97E-01 1.92E+OO u 221

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/L) (pCi/L) (pCi/ L)

TM 15 504490001 2/12/2020 Mn-54 7.68E-01 6.00E-01 1.75E+OO u TM 15 504490001 2/12/2020 Nb-95 -2.16E-01 5.61E-01 l.78E+OO u TM 15 504490001 2/12/2020 Pb-212 5.41E-01 2.57E+OO 3.18E+OO u TM 15 504490001 2/12/2020 Pb-214 6.77E-01 1.73E+OO 3.82E+OO u TM 15 504490001 2/12/2020 Ru-103 1.22E+OO 6.48E-01 l.87E+OO u TM 15 504490001 2/12/2020 Ru-106 1.64E+OO 4.51E+OO 1.49E+Ol u TM 15 504490001 2/12/2020 Sb-124 -1.43E+OO 1.22E+OO 3.54E+OO u TM 15 504490001 2/12/2020 Sb-125 6.51E-01 1.30E+OO 4.38E+OO u TM 15 504490001 2/12/2020 Se-75 -1.51E+OO 7.58E-01 2.20E+OO u TM 15 504490001 2/12/2020 Th-228 5.41E-01 2.57E+OO 3.18E+OO u TM 15 504490001 2/12/2020 Zn-65 -4.77E-01 l.38E+OO 4.58E+OO u TM 15 504490001 2/12/2020 Zr-95 -8.95E-01 1.llE+OO 3.43E+OO u TM 15 506967001 3/1112020 Ac-228 -5.39E+OO 3.81E+OO 9.40E+OO u TM 15 506967001 3/1112020 Ag-108m 1.67E+OO 1.04E+OO l.93E+OO u TM 15 506967001 3/1112020 Ag-llOm -6.60E-01 9.04E-01 2.71E+OO u TM 15 506967001 3/1112020 Ba-140 3.78E+OO 3.05E+OO l.02E+Ol u TM 15 506967001 3/1112020 Be-7 7.17E-01 5.43E+OO 1.82E+Ol u TM 15 506967001 3/1112020 Bi-214 O.OOE+OO 2.70E+OO 4.17E+OO u TM 15 506967001 3/1112020 Ce-141 1.66E+OO 2.54E+OO 3.47E+OO u TM 15 506967001 3/1112020 Ce-144 -9.62E+OO 5.02E+OO 1.38E+Ol u TM 15 506967001 3/1112020 Co-57 -6.82E-02 5.68E-01 l.85E+OO u TM 15 506967001 3/1112020 Co-58 -5.90E-01 7.21E-01 2.17E+OO u TM 15 506967001 3/1112020 Co-60 6.07E-01 7.70E-01 2.62E+OO u TM 15 506967001 3/1112020 Cr-51 2.72E-01 6.32E+OO l.95E+Ol u TM 15 506967001 3/1112020 Cs-134 5.91E-01 7.54E-01 2.48E+OO u TM 15 506967001 3/1112020 Cs-137 8.59E+OO 1.67E+OO 2.34E+OO M TM 15 506967001 3/11/2020 Fe-59 -1.69E+OO 1.56E+OO 4.80E+OO u TM 15 506967001 3/1112020 1-131 7.62E-01 9.96E-01 3.41E+OO u TM 15 506967001 3/1112020 I-131 2.70E-01 2.13E-01 6.46E-01 u TM 15 506967001 3/1112020 K-40 1.61E+03 9.24E+Ol 2.31E+Ol TM 15 506967001 3/1112020 La-140 1.48E-01 8.66E-01 2.87E+OO u TM 15 506967001 3/1112020 Mn-54 -4.94E-01 6.87E-01 2.08E+OO u TM 15 506967001 3/1112020 Nb-95 -5.07E-01 6.94E-01 2.12E+OO u TM 15 506967001 3/1112020 Pb-212 l.66E+OO 2.44E+OO 5.03E+OO u TM 15 506967001 3/1112020 Pb-214 -2.13E+OO 2.23E+OO 5.18E+OO u TM 15 506967001 3/1112020 Ru-103 -9.84E-01 7.05E-01 2.09E+OO u TM 15 506967001 3/1112020 Ru-106 -8.58E+OO 5.90E+OO l.68E+Ol u TM 15 506967001 3/1112020 Sb-124 -9.94E-02 1.34E+OO 4.31E+OO u TM 15 506967001 3/11/2020 Sb-125 5.83E-01 1.65E+OO 5.59E+OO u TM 15 506967001 311112020 Se-75 5.24E-01 9.39E-01 2.97E+OO u TM 15 506967001 3/1112020 Th-228 1.66E+OO 2.44E+OO 5.03E+OO u TM 15 506967001 3/1112020 Zn-65 1.16E+OO 1.66E+OO 5.66E+OO u TM 15 506967001 3/1112020 Zr-95 -8.59E-02 1.17E+OO 3.77E+OO u TM 15 509290001 4/9/2020 Ac-228 3.60E+OO 4.46E+OO 7.95E+OO u TM 15 509290001 4/9/2020 Ag-108m -5.03E-01 7.75E-01 1.36E+OO u TM 15 509290001 4/9/2020 Ag-llOm 1.47E+OO 7.80E-01 2.50E+OO u TM 15 509290001 4/9/2020 Ba-140 -4.57E+OO 3.50E+OO 7.67E+OO u TM 15 509290001 4/9/2020 Be-7 1.67E+OO 4.27E+OO l.41E+Ol u TM 15 509290001 4/9/2020 Bi-214 O.OOE+OO 2.38E+OO 4.33E+OO u 222

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/L) (pCi/ L) (pCi/ L)

TM 15 509290001 4/9/2020 Ce-141 -l.02E+OO 8.97E-OI 2.68E+OO u TM 15 509290001 4/9/2020 Ce-144 -7.60E-OI 3.18E+OO l.OIE+OI u TM 15 509290001 4/9/2020 Co-57 -4.65E-02 4.13E-OI l.32E+OO u TM 15 509290001 4/9/2020 Co-58 -3.14E-OI 4.71E-OI l.55E+OO u TM 15 509290001 4/9/2020 Co-60 8.86E-OI 6. I 9E-OI 2.0IE+OO u TM 15 509290001 4/9/2020 Cr-51 -3.86E+OO 4.55E+OO l.41E+OI u TM 15 509290001 4/9/2020 Cs-134 -2.29E-OI 5.29E-OI l.77E+OO u TM 15 509290001 4/9/2020 Cs-137 1.44E+OI l.43E+OO l.63E+OO M TM 15 509290001 4/9/2020 Fe-59 -2.64E-OI 1.18E+OO 3.90E+OO u TM 15 509290001 4/9/2020 I-131 -2.95E-02 7.72E-OI 2.58E+OO u TM 15 509290001 4/9/2020 I-131 -5.90E-OI 3.14E-OI 6.80E-OI u TM 15 509290001 4/9/2020 K-40 l.73E+03 8.52E+OI l.53E+OI TM 15 509290001 4/9/2020 La-140 -4.67E-OI 6.47E-OI l.96E+OO u TM 15 509290001 4/9/2020 Mn-54 7.66E-OI 5.36E-OI l.61E+OO u TM 15 509290001 4/9/2020 Nb-95 5.54E-02 5.15E-OI l.64E+OO u TM 15 509290001 4/9/2020 Pb-212 2.43E+OO l.64E+OO 2.94E+OO u TM 15 509290001 4/9/2020 Pb-214 -7.72E-OI l.77E+OO 3.84E+OO u TM 15 509290001 4/9/2020 Ru-103 -8.12E-01 5.94E-OI l.56E+OO u TM 15 509290001 4/9/2020 Ru-106 l.06E+OI 4.43E+OO l.36E+OI u TM 15 509290001 4/9/2020 Sb-124 l.04E+OO 1.1 IE+OO 3.28E+OO u TM 15 509290001 4/9/2020 Sb-125 -1.21E+OO 1.31E+OO 4.13E+OO u TM 15 509290001 4/9/2020 Se-75 4.47E-OI 6.34E-OI 2.15E+OO u TM 15 509290001 4/9/2020 Th-228 2.43E+OO l.64E+OO 2.94E+OO u TM 15 509290001 4/9/2020 Zn-65 3.00E-01 l.23E+OO 4.IOE+OO u TM 15 509290001 4/9/2020 Zr-95 -3.50E-OI 9.36E-OI 2.93E+OO u TM 15 510100001 4/22/2020 Ac-228 5.56E+OO 5.83E+OO l.60E+OI u TM 15 510100001 4/22/2020 Ag-108m -4.14E-OI 7.30E-OI 2.29E+OO u TM 15 510100001 4/22/2020 Ag-1 lOm -2.33E+OO l.55E+OO 4.45E+OO u TM 15 510100001 4/22/2020 Ba-140 -3.20E+OO 5.52E+OO l.50E+OI u TM 15 510100001 4/22/2020 Be-7 8.86E+OO 9.88E+OO 2.21E+OI u TM 15 510100001 4/22/2020 Bi-214 7.78E-OI 2.61E+OO 6.75E+OO u TM 15 510100001 4/22/2020 Ce-141 -2.36E-OI 1.28E+OO 4.39E+OO u TM 15 510100001 4/22/2020 Ce-144 4.02E+OO 5.06E+OO l.58E+OI u TM 15 510100001 4/22/2020 Co-57 3.l IE-01 6.54E-OI 2.06E+OO u TM 15 510100001 4/22/2020 Co-58 8.58E-OI l.OOE+OO 3.41E+OO u TM 15 510100001 4/22/2020 Co-60 4.74E-OI l.07E+OO 3.42E+OO u TM 15 510100001 4/22/2020 Cr-51 8.lOE+OO 7.68E+OO 2.55E+OI u TM 15 510100001 4/22/2020 Cs-134 7.77E-OI l.02E+OO 3.49E+OO u TM 15 510100001 4/22/2020 Cs-137 1.42E+OI 2.27E+OO 3.05E+OO M TM 15 510100001 4/22/2020 Fe-59 5.12E-OI 2.42E+OO 7.98E+OO u TM 15 510100001 4/22/2020 I-131 2.31E-OI 2.28E-OI 7.71E-OI u TM 15 510100001 4/22/2020 I-131 l.llE+OO l.49E+OO 4.96E+OO u TM 15 510100001 4/22/2020 K-40 l.63E+03 9.17E+Ol 3.05E+Ol TM 15 510100001 4/22/2020 La-140 -l.56E-OI l.42E+OO 4.72E+OO u TM 15 510100001 4/22/2020 Mn-54 -1.41E+OO l.OIE+OO 2.94E+OO u TM 15 510100001 4/22/2020 Nb-95 7.49E-OI 9.57E-OI 3.27E+OO u TM 15 510100001 4/22/2020 Pb-212 2.81E+OO 2.56E+OO 4.47E+OO u TM 15 510100001 4/22/2020 Pb-214 -5.29E+OO 2.77E+OO 5.81E+OO u TM 15 510100001 4/22/2020 Ru-103 1.21E+OO 9.70E-OI 3.15E+OO u TM 15 510100001 4/22/2020 Ru-106 l.94E+OO 7.95E+OO 2.73E+Ol u 223

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/L) (pCi/L) (pCi/L)

TM 15 510100001 4/22/2020 Sb-124 -l.20E+OO 2.18E+OO 5.79E+OO u TM 15 510100001 4/22/2020 Sb-125 -l.83E-01 2.99E+OO 7.46E+OO u TM 15 510100001 4/22/2020 Se-75 -8.30E-01 1.05E+OO 3.37E+OO u TM 15 510100001 4/22/2020 Th-228 2.81E+OO 2.56E+OO 4.47E+OO u TM 15 510100001 4/22/2020 Zn-65 l.51E+OO 2.45E+OO 8.16E+OO u TM 15 510100001 4/22/2020 Zr-95 -2.21E+OO 1.79E+OO 5.39E+OO u TM 15 510959001 5/6/2020 Ac-228 1.36E+OO 4.72E+OO 7.33E+OO u TM 15 510959001 5/6/2020 Ag-108m -4.07E-01 6.91E-01 1.52E+OO u TM 15 510959001 5/6/2020 Ag-llOm -2.06E-01 7.89E-01 2.59E+OO u TM 15 510959001 5/6/2020 Ba-140 -6.82E-01 2.58E+OO 8.19E+OO u TM 15 510959001 5/6/2020 Be-7 4.69E-01 4.60E+OO l.49E+Ol u TM 15 510959001 5/6/2020 Bi-214 4.26E-01 2.32E+OO 4.45E+OO u TM 15 510959001 5/6/2020 Ce-141 -l.23E+OO 9.91E-01 2.93E+OO u TM 15 510959001 5/6/2020 Ce-144 2.39E+OO 3.46E+OO 1.IOE+Ol u TM 15 510959001 5/6/2020 Co-57 -6.54E-02 4.44E-01 1.41E+OO u TM 15 510959001 5/6/2020 Co-58 -3.76E-01 5.71E-01 1.85E+OO u TM 15 510959001 5/6/2020 Co-60 2.94E-01 5.97E-01 2.04E+OO u TM 15 510959001 5/6/2020 Cr-51 -2.56E+OO 4.62E+OO l.51E+Ol u TM 15 510959001 5/6/2020 Cs-134 2.02E-01 6.02E-01 2.03E+OO u TM 15 510959001 5/6/2020 Cs-137 l.24E+Ol 1.44E+OO 1.74E+OO M TM 15 510959001 5/6/2020 Fe-59 -l.58E+OO 1.27E+OO 3.76E+OO u TM 15 510959001 5/6/2020 I-131 l.69E-01 1.84E-01 6.08E-01 u TM 15 510959001 5/6/2020 I-131 5.34E-01 9.09E-01 2.71E+OO u TM 15 510959001 5/6/2020 K-40 l.73E+03 8.45E+Ol 1.67E+Ol TM 15 510959001 5/6/2020 La-140 -4.82E-01 7.95E-01 2.54E+OO u TM 15 510959001 5/6/2020 Mn-54 7.48E-01 5.68E-01 1.87E+OO u TM 15 510959001 5/6/2020 Nb-95 O.OOE+OO 1.21E+OO l.69E+OO u TM 15 510959001 5/6/2020 Pb-212 3.19E+OO 2.33E+OO 3.64E+OO u TM 15 510959001 5/6/2020 Pb-214 -6.19E-01 1.64E+OO 4.08E+OO u TM 15 510959001 5/6/2020 Ru-103 -6.39E-01 5.84E-01 1.67E+OO u TM 15 510959001 5/6/2020 Ru-106 -5.09E-01 4.80E+OO 1.52E+Ol u TM 15 510959001 5/6/2020 Sb-124 5.lOE-01 1.09E+OO 3.69E+OO u TM 15 510959001 5/6/2020 Sb-125 1.15E+OO 1.61E+OO 4.74E+OO u TM 15 510959001 5/6/2020 Se-75 3.72E-01 6.86E-01 2.32E+OO u TM 15 510959001 5/6/2020 Th-228 3.19E+OO 2.33E+OO 3.64E+OO u TM 15 510959001 5/6/2020 Zn-65 -5.21E+OO 2.22E+OO 4.15E+OO u TM 15 510959001 5/6/2020 Zr-95 3.95E-01 1.08E+OO 3.24E+OO u TM 15 511872001 5/20/2020 Ac-228 -5.71E+OO 4.49E+OO 9.30E+OO u TM 15 511872001 5/20/2020 Ag-108m -4.17E-01 5.49E-01 l.69E+OO u TM 15 511872001 5/20/2020 Ag-11 Om -2.93E-01 8.88E-01 2.80E+OO u TM 15 511872001 5/20/2020 Ba-140 -1.30E-01 2.42E+OO 8.00E+OO u TM 15 511872001 5/20/2020 Be-7 7.15E-01 4.91E+OO l.64E+Ol u TM 15 511872001 5/20/2020 Bi-214 3.97E+OO 3.21E+OO 5.29E+OO u TM 15 511872001 5/20/2020 Ce-141 -5.50E-01 l.09E+OO 3.44E+OO u TM 15 511872001 5/20/2020 Ce-144 -9.37E-01 4.20E+OO 1.34E+Ol u TM 15 511872001 5/20/2020 Co-57 1.0IE+OO 6.02E-01 1.84E+OO u TM 15 511872001 5/20/2020 Co-58 -8.37E-01 7.37E-01 l.91E+OO u TM 15 511872001 5/20/2020 Co-60 1.26E+OO 7.58E-01 2.51E+OO u TM 15 511872001 5/20/2020 Cr-51 -9.79E+OO 7.06E+OO 1.72E+Ol u 224

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/L) (pCi/ L) (pCi/ L)

TM 15 511872001 5/20/2020 Cs-134 l.06E+OO 7.38E-Ol 2.37E+OO u TM 15 511872001 5/20/2020 Cs-137 l.02E+Ol l.64E+OO l.85E+OO M TM 15 511872001 5/20/2020 Fe-59 -3.43E-Ol l.39E+OO 4.66E+OO u TM 15 511872001 5/20/2020 1-131 5.47E-02 l.80E-Ol 5.88E-Ol u TM 15 511872001 5/20/2020 1-131 -2.84E-Ol 7.53E-Ol 2.52E+OO u TM 15 511872001 5/20/2020 K-40 l.61E+03 9.89E+Ol l.97E+Ol TM 15 511872001 5/20/2020 La-140 -5.88E-Ol 7.80E-Ol 2.41E+OO u TM 15 511872001 5/20/2020 Mn-54 6.30E-Ol 6.19E-Ol 2.0IE+OO u TM 15 511872001 5/20/2020 Nb-95 -2.23E-02 5.62E-Ol l.81E+OO u TM 15 511872001 5/20/2020 Pb-212 -4.78E-Ol l.88E+OO 4.31E+OO u TM 15 511872001 5/20/2020 Pb-214 -3.44E+OO 2.45E+OO 4.74E+OO u TM 15 511872001 5/20/2020 Ru-103 -2.78E-Ol 5.83E-Ol l.90E+OO u TM 15 511872001 5/20/2020 Ru-106 l.39E+Ol 7.26E+OO l.65E+Ol u TM 15 511872001 5/20/2020 Sb-124 -8.17E-02 l.l9E+OO 3.87E+OO u TM 15 511872001 5/20/2020 Sb-125 2.09E+OO l.69E+OO 5.62E+OO u TM 15 511872001 5/20/2020 Se-75 -l.28E-Ol 7.61E-Ol 2.61E+OO u TM 15 511872001 5/20/2020 Th-228 -4.78E-Ol l.88E+OO 4.31E+OO u TM 15 511872001 5/20/2020 Zn-65 4.34E-Ol l.47E+OO 5.0lE+OO u TM 15 511872001 5/20/2020 Zr-95 -l.44E+OO l.l5E+OO 3.39E+OO u TM 15 512892001 6/3/2020 Ac-228 -2.85E+OO 4.63E+OO 9.96E+OO u TM 15 512892001 6/3/2020 Ag-108m l.l2E+OO 5.76E-Ol l.77E+OO u TM 15 512892001 6/3/2020 Ag-llOm 6.86E-Ol l.20E+OO 3.56E+OO u TM 15 512892001 6/3/2020 Ba-140 7.61E-Ol 3.39E+OO l.09E+Ol u TM 15 512892001 6/3/2020 Be-7 7.86E+OO 5.83E+OO l.86E+Ol u TM 15 512892001 6/3/2020 Bi-214 -2.90E+OO 2.32E+OO 4.53E+OO u TM 15 512892001 6/3/2020 Ce-141 7.56E-Ol 9.62E-Ol 2.98E+OO u TM 15 512892001 6/3/2020 Ce-144 -2.21E+OO 3.69E+OO l. l3E+Ol u TM 15 512892001 6/3/2020 Co-57 -4.72E-Ol 5.78E-Ol l.42E+OO u TM 15 512892001 6/3/2020 Co-58 -9.77E-02 7.lOE-01 2.36E+OO u TM 15 512892001 6/3/2020 Co-60 8.98E-Ol 7.56E-Ol 2.48E+OO u TM 15 512892001 6/3/2020 Cr-51 -2.lOE+OO 5.09E+OO l.66E+Ol u TM 15 512892001 6/3/2020 Cs-134 -5.57E-02 7.74E-Ol 2.58E+OO u TM 15 512892001 6/3/2020 Cs-137 5.06E+OO l.47E+OO 2.20E+OO M TM 15 512892001 6/3/2020 Fe-59 3.78E+OO l.90E+OO 5.92E+OO u TM 15 512892001 6/3/2020 1-131 -l.05E-Ol l.55E-Ol 5. l IE-01 u TM 15 512892001 6/3/2020 1-131 -l.40E+OO l.46E+OO 3.64E+OO u TM 15 512892001 6/3/2020 K-40 l.58E+03 8.08E+Ol l.95E+Ol TM 15 512892001 6/3/2020 La-140 -5.58E-Ol l.OIE+OO 3.24E+OO u TM 15 512892001 6/3/2020 Mn-54 6.00E-01 7.09E-Ol 2.38E+OO u TM 15 512892001 6/3/2020 Nb-95 l.09E+OO 7.49E-Ol 2.48E+OO u TM 15 512892001 6/3/2020 Pb-212 l.62E+OO 2.08E+OO 3.89E+OO u TM 15 512892001 6/3/2020 Pb-214 -2.16E+OO 2.31E+OO 4.31E+OO u TM 15 512892001 6/3/2020 Ru-103 -2.62E-02 6.80E-Ol 2.18E+OO u TM 15 512892001 6/3/2020 Ru-106 -l.80E+OO 5.84E+OO l.96E+Ol u TM 15 512892001 6/3/2020 Sb-124 6.70E-Ol l.33E+OO 4.55E+OO u TM 15 512892001 6/3/2020 Sb-125 3.19E+OO l.74E+OO 5.39E+OO u TM 15 512892001 6/3/2020 Se-75 8.84E-02 7.37E-Ol 2.47E+OO u TM 15 512892001 6/3/2020 Th-228 l.62E+OO 2.08E+OO 3.89E+OO u TM 15 512892001 6/3/2020 Zn-65 l.61E+OO l.93E+OO 5.64E+OO u TM 15 512892001 6/3/2020 Zr-95 -l.03E+OO l.22E+OO 3.91E+OO u 225

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/L) (pCi/L) (pCi/L)

TM 15 514054001 6/17/2020 Ac-228 -2.86E+OO 4.57E+OO 1.02E+Ol u TM 15 514054001 6/17/2020 Ag-l08m 4.34E-02 5.41E-Ol l.73E+OO u TM 15 514054001 6/17/2020 Ag-1 lOm -2.06E-Ol 8.63E-Ol 2.80E+OO u TM 15 514054001 6/17/2020 Ba-140 -9.96E-Ol 2.25E+OO 7.48E+OO u TM 15 514054001 6/17/2020 Be-7 3.15E+OO 5.19E+OO l.66E+Ol u TM 15 514054001 6/17/2020 Bi-214 -l.28E+OO 2.29E+OO 4.76E+OO u TM 15 514054001 6/17/2020 Ce-141 -l.40E+OO l.02E+OO 3.22E+OO u TM 15 514054001 6/17/2020 Ce-144 -4.30E+OO 4.0IE+OO l.31E+Ol u TM 15 514054001 6/17/2020 Co-57 4.lOE-01 5.32E-Ol l.81E+OO u TM 15 514054001 6/17/2020 Co-58 -2.28E-02 6.15E-Ol 2.02E+OO u TM 15 514054001 6/17/2020 Co-60 -6.29E-Ol 7.24E-Ol 2.29E+OO u TM 15 514054001 6/17/2020 Cr-51 -2.52E+OO 4.92E+OO l.58E+Ol u TM 15 514054001 6/17/2020 Cs-134 -3.90E-Ol 6.67E-Ol 2.13E+OO u TM 15 514054001 6/17/2020 Cs-137 l.29E+Ol l.44E+OO 2.06E+OO M TM 15 514054001 6/17/2020 Fe-59 -1.62E+OO l.49E+OO 4.43E+OO u TM 15 514054001 6/17/2020 1-131 -5.02E-Ol l.OIE+OO 2.41E+OO u TM 15 514054001 6/17/2020 1-131 4.8IE-Ol 2.71E-Ol 7.97E-Ol u TM 15 514054001 6/17/2020 K-40 l.54E+03 7.91E+Ol l.96E+Ol TM 15 514054001 6/17/2020 La-140 -6.47E-Ol 7.04E-Ol 2.14E+OO u TM 15 514054001 6/17/2020 Mn-54 -1.83E-Ol 6.30E-Ol 2.05E+OO u TM 15 514054001 6/17/2020 Nb-95 5.02E-02 6.41E-Ol 1.97E+OO u TM 15 514054001 6/17/2020 Pb-212 1.28E+OO 2.39E+OO 4.48E+OO u TM 15 514054001 6/17/2020 Pb-214 -2.26E+OO 2.63E+OO 4.74E+OO u TM 15 514054001 6/17/2020 Ru-103 4.65E-Ol 6.14E-Ol l.96E+OO u TM 15 514054001 6/17/2020 Ru-106 4.76E-Ol 5.70E+OO l.92E+Ol u TM 15 514054001 6/17/2020 Sb-124 -6.90E-02 l.66E+OO 3.12E+OO u TM 15 514054001 6/17/2020 Sb-125 -l.42E+OO l.75E+OO 5.37E+OO u TM 15 514054001 6/17/2020 Se-75 1.02E+OO 8.18E-Ol 2.65E+OO u TM 15 514054001 6/17/2020 Th-228 l.28E+OO 2.39E+OO 4.48E+OO u TM 15 514054001 6/17/2020 Zn-65 -1.00E+OO l.62E+OO 5.02E+OO u TM 15 514054001 6/17/2020 Zr-95 -l.64E-Ol l.18E+OO 3.40E+OO u TM 15 515125001 7/1/2020 Ac-228 -5.52E+OO 4.06E+OO 9.16E+OO u TM 15 515125001 7/1/2020 Ag-108m 2.26E-02 4.98E-Ol l.66E+OO u TM 15 515125001 7/1/2020 Ag-llOm l.06E+OO 9.08E-Ol 3.06E+OO u TM 15 515125001 7/1/2020 Ba-140 3.31E+OO 3.03E+OO 9.94E+OO u TM 15 515125001 711/2020 Be-7 -4.19E+OO 5.31E+OO l.69E+Ol u TM 15 515125001 7/1/2020 Bi-214 O.OOE+OO 2.94E+OO 4.81E+OO u TM 15 515125001 7/1/2020 Ce-141 -2.92E+OO l.66E+OO 3.29E+OO u TM 15 515125001 7/1/2020 Ce-144 -4.69E+OO 4.0IE+OO l.23E+Ol u TM 15 515125001 7/1/2020 Co-57 -l.3 IE-01 5.02E-Ol l.63E+OO u TM 15 515125001 7/1/2020 Co-58 -3.33E-02 6.61E-Ol 2.09E+OO u TM 15 515125001 7/1/2020 Co-60 -6.42E-02 8.28E-Ol 2.69E+OO u TM 15 515125001 7/1/2020 Cr-51 -2.22E-Ol 5.llE+OO l.74E+Ol u TM 15 515125001 7/1/2020 Cs-134 -7.70E-Ol 7.39E-Ol 2.18E+OO u TM 15 515125001 7/1/2020 Cs-137 l.34E+Ol l.54E+OO 2.12E+OO M TM 15 515125001 7/1/2020 Fe-59 l.32E+OO 2.42E+OO 5.53E+OO u TM 15 515125001 7/1/2020 1-131 2.33E-Ol 2.9IE-Ol 9.97E-Ol u TM 15 515125001 7/1/2020 1-131 -l.06E+OO 9.91E-Ol 3.15E+OO u TM 15 515125001 7/1/2020 K-40 l.71E+03 l.05E+02 l.84E+Ol TM 15 515125001 7/1/2020 La-140 9.85E-Ol l.02E+OO 3.37E+OO u 226

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/L) (pCi/ L) (pCi/ L)

TM 15 515125001 7/1/2020 Mn-54 1.16£-01 6.27£-01 1.90E+OO u TM 15 515125001 7/1/2020 Nb-95 8.71£-01 6.91 E-01 2.20E+OO u TM 15 515125001 7/1/2020 Pb-212 1.06E+OO 2.46E+OO 4.22E+OO u TM 15 515125001 7/1/2020 Pb-214 4.39£-01 1.27E+OO 4.32E+OO u TM 15 515125001 7/1/2020 Ru-103 -4.45£-01 6.05£-01 1.92£+00 u TM 15 515125001 71112020 Ru-106 7.06£-01 5.52E+OO J.79E+OI u TM 15 515125001 7/1/2020 Sb-124 -5.57£-01 1.20E+OO 3.92E+OO u TM 15 515125001 71112020 Sb-125 6.82£-01 1.56£+00 5.24E+OO u TM 15 515125001 71112020 Se-75 2.87£-01 8.25£-01 2.58E+OO u TM 15 515125001 71112020 Th-228 1.06E+OO 2.46E+OO 4.22E+OO u TM 15 515125001 71112020 Zn-65 3.18E+OO 1.74£+00 5.55E+OO u TM 15 515125001 7/1/2020 Zr-95 5.29£-01 1.1 lE+OO 3.59E+OO u TM 15 517177001 7/29/2020 Ac-228 4.18E+OO 4.44£+00 8.48£+00 u TM 15 517177001 7/29/2020 Ag-108m 4.35£-01 5.39£-01 1.80E+OO u TM 15 517177001 7/29/2020 Ag-1 IOm -2.68£-02 8.30£-01 2.80E+OO u TM 15 517177001 7/29/2020 Ba-140 -1.00E+01 5.59£+00 9.19£+00 u TM 15 517177001 7/29/2020 Be-7 3.38E+OO 5.12£+00 1.71£+01 u TM 15 517177001 7/29/2020 Bi-214 2.90£+00 3.08E+OO 4.52E+OO u TM 15 517177001 7/29/2020 Ce-141 -2.95£-01 l.08E+OO 3.19E+OO u TM 15 517177001 7/29/2020 Ce-144 -7.67£+00 5.90E+OO 1.26E+OI u TM 15 517177001 7/29/2020 Co-57 -2.15£-01 5.02£-01 1.62E+OO u TM 15 517177001 7/29/2020 Co-58 -4.09£-01 6.97£-01 2.14E+OO u TM 15 517177001 7/29/2020 Co-60 1.78£-01 7.24£-01 2.38E+OO u TM 15 517177001 7/29/2020 Cr-51 -3.38E+OO 5.30E+OO 1. 76E+Ol u TM 15 517177001 7 /29/2020 Cs-134 8.60£-01 7.50£-01 2.40E+OO u TM 15 517177001 7/29/2020 Cs-137 3.42E+OO l.12E+OO 2.17E+OO M TM 15 517177001 7/29/2020 Fe-59 -1.27E+OO 1.58E+OO 5.02E+OO u TM 15 517177001 7/29/2020 1-131 1.59£-01 1.33£-01 4.25£-01 u TM 15 517177001 7/29/2020 1-131 6.46£-01 9.82£-01 3.32E+OO u TM 15 517177001 7/29/2020 K-40 1.72E+03 1.05£+02 2.04E+Ol TM 15 517177001 7/29/2020 La-140 6.47£-01 9.46£-01 2.79E+OO u TM 15 517177001 7/29/2020 Mn-54 -3.00E-01 6.33£-01 2.llE+OO u TM 15 517177001 7 /29/2020 Nb-95 8.74£-01 6.76£-01 2.15E+OO u TM 15 517177001 712912020 Pb-212 2.54E+OO 2.52E+OO 4.21E+OO u TM 15 517177001 7/29/2020 Pb-214 1.10£+00 1.33£+00 4.48£+00 u TM 15 517177001 7/29/2020 Ru- I 03 -1.08E+OO 6.95£-01 2.04E+OO u TM 15 517177001 7/29/2020 Ru- I 06 1.28E+OO 5.40E+OO 1.76E+Ol u TM 15 517177001 7/29/2020 Sb-124 3.72£-01 1.3 lE+OO 4.47E+OO u TM 15 517177001 7/29/2020 Sb-125 -2.74E+OO 1.70£+00 5.02E+OO u TM 15 517177001 7/29/2020 Se-75 1.74£+00 8.89£-01 2.59£+00 u TM 15 517177001 712912020 Th-228 2.54E+OO 2.52£+00 4.21E+OO u TM 15 517177001 7/29/2020 Zn-65 -5.40£-01 1.68£+00 5.48E+OO u TM 15 517177001 7/29/2020 Zr-95 2.63£-01 l.17E+OO 3.76£+00 u TM 15 518830001 8/12/2020 Ac-228 6.23£+00 5.96E+OO 9.43E+OO u TM 15 518830001 8/12/2020 Ag-108m 9.66£-01 6.94£-01 1.64E+OO u TM 15 518830001 8/12/2020 Ag-llOm -1.50£-01 8.17£-01 2.62E+OO u TM 15 518830001 8/12/2020 Ba-140 -3.56E+OO 3.00E+OO 9.09E+OO u TM 15 518830001 8/12/2020 Be-7 -2.18E+OO 4.80E+OO 1.55£+01 u TM 15 518830001 8/12/2020 Bi-214 -2.56E+OO 3.35E+OO 4.88£+00 u 227

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/L) (pCi/ L) (pCi/ L)

TM 15 518830001 8/12/2020 Ce-141 2.49E+OO l.29E+OO 3.66E+OO u TM 15 518830001 8/12/2020 Ce-144 l.78E+OO 4.06E+OO l.38E+Ol u TM 15 518830001 8/12/2020 Co-57 -9.92E-02 5.23E-Ol 1.77E+OO u TM 15 518830001 8/12/2020 Co-58 -2.77E-02 5.88E-Ol 1.90E+OO u TM 15 518830001 8/12/2020 Co-60 1.1 lE+OO 7.68E-Ol 2.46E+OO u TM 15 518830001 8/12/2020 Cr-51 l.68E+OO 5.51E+OO 1.84E+Ol u TM 15 518830001 8/12/2020 Cs-134 2.20E+OO l.35E+OO 2.41E+OO u TM 15 518830001 8/12/2020 Cs-137 4.80E+OO l.21E+OO l.88E+OO M TM 15 518830001 8/12/2020 Fe-59 -6.85E-02 l.38E+OO 4.41E+OO u TM 15 518830001 8/12/2020 I-131 2.29E+OO l.15E+OO 3.56E+OO u TM 15 518830001 8/12/2020 I-131 -2.81E-Ol 3.17E-Ol 9.81E-Ol u TM 15 518830001 8/12/2020 K-40 l.44E+03 8.51E+Ol 2.06E+Ol TM 15 518830001 8/12/2020 La-140 -2.80E-Ol 9.58E-Ol 3.08E+OO u TM 15 518830001 8/12/2020 Mn-54 2.25E-Ol 6.46E-Ol 1.89E+OO u TM 15 518830001 8/12/2020 Nb-95 l.26E+OO 7.llE-01 2.23E+OO u TM 15 518830001 8/12/2020 Pb-212 -2.45E+OO l.84E+OO 4.30E+OO u TM 15 518830001 8/12/2020 Pb-214 l.05E+OO 3.lOE+OO 4.91E+OO u TM 15 518830001 8/12/2020 Ru-103 -4.54E-Ol 6.87E-Ol 1.95E+OO u TM 15 518830001 8/12/2020 Ru-106 -2.78E+OO 5.41E+OO l.73E+Ol u TM 15 518830001 8/12/2020 Sb-124 6.42E-Ol l.38E+OO 4.25E+OO u TM 15 518830001 8/12/2020 Sb-125 -3.59E-Ol l.52E+OO 4.99E+OO u TM 15 518830001 8/12/2020 Se-75 4.16E-Ol 8.18E-Ol 2.75E+OO u TM 15 518830001 8/12/2020 Th-228 -2.45E+OO l.84E+OO 4.30E+OO u TM 15 518830001 8/12/2020 Zn-65 -6.13E-02 l.61E+OO 4.57E+OO u TM 15 518830001 8/12/2020 Zr-95 2.40E-Ol l.09E+OO 3.55E+OO u TM 15 519927001 8/26/2020 Ac-228 -5.03E+OO 4.04E+OO 8.83E+OO u TM 15 519927001 8/26/2020 Ag-108m 5.05E-02 5.19E-Ol l.67E+OO u TM 15 519927001 8/26/2020 Ag-llOm 4.51E-Ol 8.50E-Ol 2.84E+OO u TM 15 519927001 8/26/2020 Ba-140 -2.86E+OO 3.07E+OO 9.18E+OO u TM 15 519927001 8/26/2020 Be-7 9.54E+OO 9.63E+OO l.19E+Ol u TM 15 519927001 8/26/2020 Bi-214 3.66E+OO 2.52E+OO 5.0lE+OO u TM 15 519927001 8/26/2020 Ce-141 -4.lOE-01 l.03E+OO 3.46E+OO u TM 15 519927001 8/26/2020 Ce-144 -2.16E+OO 3.80E+OO 1.27E+Ol u TM 15 519927001 8/26/2020 Co-57 -1.76E-02 5.31E-Ol l.63E+OO u TM 15 519927001 8/26/2020 Co-58 -3.63E-Ol 5.69E-Ol l.83E+OO u TM 15 519927001 8/26/2020 Co-60 8.06E-Ol 7.31E-Ol 2.39E+OO u TM 15 519927001 8/26/2020 Cr-51 l.41E+OO 5.43E+o0 l.78E+Ol u TM 15 519927001 8/26/2020 Cs-134 -7.74E-Ol 6.97E-Ol 2.15E+OO u TM 15 519927001 8/26/2020 Cs-137 2.03E+OO 8.12E-Ol 2.41E+OO u TM 15 519927001 8/26/2020 Fe-59 4.56E-Ol l.54E+OO 5.05E+OO u TM 15 519927001 8/26/2020 I-131 l.93E-Ol 3.48E-Ol l.02E+OO UDL TM 15 519927001 8/26/2020 I-131 5.35E-Ol l.lOE+OO 3.59E+OO u TM 15 519927001 8/26/2020 K-40 l.73E+03 9.33E+Ol l.64E+Ol TM 15 519927001 8/26/2020 La-140 -l.54E+OO 8.73E-Ol 2.32E+OO u TM 15 519927001 8/26/2020 Mn-54 -2.30E-Ol 5.93E-Ol l.93E+OO u TM 15 519927001 8/26/2020 Nb-95 -5.63E-Ol 6.31E-Ol 2.00E+OO u TM 15 519927001 8/26/2020 Pb-212 3.95E+OO 2.37E+OO 4.16E+OO u TM 15 519927001 8/26/2020 Pb-214 -2.42E+OO 2.04E+OO 4.61E+OO u TM 15 519927001 8/26/2020 Ru-103 5.97E-Ol 6.62E-Ol 2.12E+OO u TM 15 519927001 8/26/2020 Ru-106 6.50E+OO 5.44E+OO 1.83E+Ol u 228

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/L) (pCi/ L) (pCi/ L)

TM 15 519927001 8/26/2020 Sb-124 -3.08E-01 1.38E+OO 3.90E+OO u TM 15 519927001 8/26/2020 Sb-125 -7. l IE-01 1.65E+OO 5.22E+OO u TM 15 519927001 8/26/2020 Se-75 -1.09E-02 7.88E-01 2.60E+OO u TM 15 519927001 8/26/2020 Th-228 3.95E+OO 2.37E+OO 4.16E+OO u TM 15 519927001 8/26/2020 Zn-65 -1.32E+OO 1.51E+OO 4.63E+OO u TM 15 519927001 8/26/2020 Zr-95 -1.21E+OO 1.09E+OO 3.39E+OO u TM 15 521477001 9/9/2020 Ac-228 -9.24E-01 2.90E+OO 6.09E+OO u TM 15 521477001 9/9/2020 Ag-108m 1.35E-02 3.15E-01 l.06E+OO u TM 15 521477001 9/9/2020 Ag-llOm -7.48E-02 5.46E-01 1.75E+OO u TM 15 521477001 9/9/2020 Ba-140 9.41E-01 1.90E+OO 6.39E+OO u TM 15 521477001 9/9/2020 Be-7 -5.63E-01 3.0IE+OO 1.0IE+Ol u TM 15 521477001 9/9/2020 Bi-214 4.59E-01 2.30E+OO 2.81E+OO u TM 15 521477001 9/9/2020 Ce-141 -1.65E-01 7.IOE-01 2.llE+OO u TM 15 521477001 9/9/2020 Ce-144 -2.14E+OO 2.56E+OO 8.02E+OO u TM 15 521477001 9/9/2020 Co-57 8.34E-01 3.69E-01 l.06E+OO u TM 15 521477001 9/9/2020 Co-58 3.93E-01 4.03E-01 1.32E+OO u TM 15 521477001 9/9/2020 Co-60 -2.83E-01 4.53E-01 1.47E+OO u TM 15 521477001 9/9/2020 Cr-51 1.13E-01 3.43E+OO l.18E+Ol u TM 15 521477001 9/9/2020 Cs-134 5.26E-01 4.67E-01 1.51E+OO u TM 15 521477001 9/9/2020 Cs-137 3.86E+OO 9.82E-01 1.30E+OO M TM 15 521477001 9/9/2020 Fe-59 -1.17E+OO 1.08E+OO 3.18E+OO u TM 15 521477001 9/9/2020 I-131 -3.19E-01 6.96E-01 2.34E+OO u TM 15 521477001 9/9/2020 I-131 -3.36E-01 2.85E-01 5.87E-01 u TM 15 521477001 9/9/2020 K-40 1.62E+03 7.86E+Ol l.13E+Ol TM 15 521477001 9/9/2020 La-140 -8.03E-02 5.43E-01 1.79E+OO u TM 15 521477001 9/9/2020 Mn-54 -4.64E-01 4.21E-01 1.27E+OO u TM 15 521477001 9/9/2020 Nb-95 -7.69E-01 5.80E-01 1.30E+OO u TM 15 521477001 9/9/2020 Pb-212 -1.27E+OO 1.19E+OO 2.58E+OO u TM 15 521477001 9/9/2020 Pb-214 1.15E+OO 1.76E+OO 2.88E+OO u TM 15 521477001 9/9/2020 Ru-103 -3.75E-01 4.53E-01 1.30E+OO u TM 15 521477001 9/9/2020 Ru-106 -9.30E-01 3.27E+OO 1.07E+Ol u TM 15 521477001 9/9/2020 Sb-124 -4.12E-01 9.19E-01 2.71E+OO u TM 15 521477001 9/9/2020 Sb-125 -1.03E+OO 9.77E-01 3.13E+OO u TM 15 521477001 9/9/2020 Se-75 9.85E-01 5.66E-01 1.68E+OO u TM 15 521477001 9/9/2020 Th-228 -1.27E+OO 1.19E+OO 2.58E+OO u TM 15 521477001 9/9/2020 Zn-65 -5.71E-01 9.97E-01 3.07E+OO u TM 15 521477001 9/9/2020 Zr-95 4.32E-01 7.20E-01 2.37E+OO u TM 15 522474001 9/23/2020 Ac-228 -7.24E+OO 4.02E+OO 8.85E+OO u TM 15 522474001 9/23/2020 Ag-108m -3.26E-01 5.06E-01 l.64E+OO u TM 15 522474001 9/23/2020 Ag-1 lOm -1.67E+OO 9.15E-Ol 2.40E+OO u TM 15 522474001 9/23/2020 Ba-140 2.32E+OO 2.58E+OO 8.56E+OO u TM 15 522474001 9/23/2020 Be-7 -2.26E+OO 4.55E+OO 1.47E+Ol u TM 15 522474001 9/23/2020 Bi-214 -2.74E+OO 2.03E+OO 4.22E+OO u TM 15 522474001 9/23/2020 Ce-141 -7.75E-01 9.89E-01 3.02E+OO u TM 15 522474001 9/23/2020 Ce-144 1.23E+OO 3.84E+OO 1.22E+Ol u TM 15 522474001 9/23/2020 Co-57 -9.99E-02 5.02E-01 l.59E+OO u TM 15 522474001 9/23/2020 Co-58 5.17E-01 5.90E-01 1.93E+OO u TM 15 522474001 9/23/2020 Co-60 l.33E-01 6.70E-01 2.25E+OO u TM 15 522474001 9/23/2020 Cr-51 1.08E+Ol 5.52E+OO l.74E+Ol u 229

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/L) (pCi/L) (pCi/L)

TM 15 522474001 9/23/2020 Cs-134 l.12E+OO 7.00E-01 2.23E+OO u TM 15 522474001 9/23/2020 Cs-137 O.OOE+OO l.02E+OO 1.88E+OO u TM 15 522474001 9/23/2020 Fe-59 1.06E-02 1.34E+OO 4.54E+OO u TM 15 522474001 9/23/2020 1-131 3.07E-02 1.27E-01 4.14E-01 u TM 15 522474001 9/23/2020 1-131 1.07E+OO 8.84E-01 2.94E+OO u TM 15 522474001 9/23/2020 K-40 1.71E+03 9.03E+Ol 1.73E+Ol TM 15 522474001 9/23/2020 La-140 -8.43E-01 8.22E-01 2.44E+OO u TM 15 522474001 9/23/2020 Mn-54 -6.83E-01 6.12E-01 l.80E+OO u TM 15 522474001 9/23/2020 Nb-95 -2.19E-03 5.85E~Ol 1.89E+OO u TM 15 522474001 9/23/2020 Pb-212 2.84E-01 2.llE+OO 3.97E+OO u TM 15 522474001 9/23/2020 Pb-214 -1.llE+OO 1.99E+OO 4.25E+OO u TM 15 522474001 9/23/2020 Ru-103 6.95E-01 6.04E-01 1.81E+OO u TM 15 522474001 9/23/2020 Ru-106 -8.26E+OO 5.42E+OO 1.55E+Ol u TM 15 522474001 9/23/2020 Sb-124 -6.62E-02 1.20E+OO 3.91E+OO u TM 15 522474001 9/23/2020 Sb-125 -1.02E+OO 1.49E+OO 4.79E+OO u TM 15 522474001 9/23/2020 Se-75 -3.81E-01 7.lOE-01 2.38E+OO u TM 15 522474001 9/23/2020 Th-228 2.84E-01 2.llE+OO 3.97E+OO u TM 15 522474001 9/23/2020 Zn-65 1.27E+OO 1.42E+OO 4.86E+OO u TM 15 522474001 9/23/2020 Zr-95 -8.79E-01 1.0IE+OO 3.08E+OO u TM 15 523902001 1017/2020 Ac-228 9.27E+OO 7.45E+OO 1.52E+Ol u TM 15 523902001 1017/2020 Ag-108m 2.12E+OO 8.92E-01 2.75E+OO u TM 15 523902001 1017/2020 Ag-llOm -2.17E+OO 1.33E+OO 3.52E+OO u TM 15 523902001 1017/2020 Ba-140 1.29E+Ol 5.52E+OO 1.38E+Ol u TM 15 523902001 1017/2020 Be-7 4.98E+OO 7.20E+OO 2.46E+Ol u TM 15 523902001 1017/2020 Bi-214 -6.76E-02 3.27E+OO 8.29E+OO u TM 15 523902001 1017/2020 Ce-141 -2.88E+OO 1.86E+OO 4.59E+OO u TM 15 523902001 1017/2020 Ce-144 1.02E+OO 5.39E+OO 1.79E+Ol u TM 15 523902001 1017/2020 Co-57 -1.09E+OO 9.23E-01 2.29E+OO u TM 15 523902001 1017/2020 Co-58 -3.43E-01 1.08E+OO 3.28E+OO u TM 15 523902001 1017/2020 Co-60 -6.26E-01 1.00E+OO 3.17E+OO u TM 15 523902001 1017/2020 Cr-51 -1.04E+Ol 9.12E+OO 2.41E+Ol u TM 15 523902001 1017/2020 Cs-134 l.IOE+OO 1.09E+OO 3.61E+OO u TM 15 523902001 1017/2020 Cs-137 3.43E-01 9.03E-01 3.02E+OO u TM 15 523902001 1017/2020 Fe-59 1.29E-01 2.27E+OO 7.73E+OO u TM 15 523902001 1017/2020 1-131 -1.79E+OO l.86E+OO 5.41E+OO u TM 15 523902001 1017/2020 1-131 -2.31E-01 3.67E-01 l.16E+OO UDL TM 15 523902001 1017/2020 K-40 1.68E+03 9.66E+Ol 3.14E+Ol TM 15 523902001 1017/2020 La-140 4.79E-01 1.47E+OO 4.96E+OO u TM 15 523902001 1017/2020 Mn-54 4.05E-01 9.58E-01 3.15E+OO u TM 15 523902001 1017/2020 Nb-95 -6.68E-01 1.24E+OO 3.12E+OO u TM 15 523902001 1017/2020 Pb-212 5.61E+OO 3.81E+OO 6.21E+OO u TM 15 523902001 1017/2020 Pb-214 5.29E+OO 4.40E+OO 7.32E+OO u TM 15 523902001 1017/2020 Ru-103 -9.30E-01 9.09E-01 2.86E+OO u TM 15 523902001 1017/2020 Ru-106 -3.36E-02 7.50E+OO 2.49E+Ol u TM 15 523902001 1017/2020 Sb-124 -2.0IE+OO 2.18E+OO 6.35E+OO u TM 15 523902001 1017/2020 Sb-125 -1.85E+OO 2.15E+OO 6.95E+OO u TM 15 523902001 1017/2020 Se-75 2.52E-Ol l.17E+OO 3.76E+OO u TM 15 523902001 1017/2020 Th-228 5.61E+OO 3.81E+OO 6.21E+OO u TM 15 523902001 1017/2020 Zn-65 -4.62E+OO 2.52E+OO 7.02E+OO u TM 15 523902001 1017/2020 Zr-95 -2.60E-01 l.60E+OO 5.16E+OO u 230

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/L) (pCi/ L) (pCi/ L)

TM 15 527400001 11/4/2020 Ac-228 1.14E+OO 5.70E+OO l.09E+Ol u TM 15 527400001 11/4/2020 Ag-108m 3.72E-01 5.93E-01 l.98E+OO u TM 15 527400001 11/4/2020 Ag-llOm -2. l IE-01 9.43E-01 3.0IE+OO u TM 15 527400001 11/4/2020 Ba-140 -3.34E+OO 4.66E+OO l.47E+Ol u TM 15 527400001 11/4/2020 Be-7 -2.94E-01 5.71E+OO l.88E+Ol u TM 15 527400001 11/4/2020 Bi-214 3.23E+OO 2.60E+OO 3.70E+OO u TM 15 527400001 11/4/2020 Ce-141 8.04E-01 2.21E+OO 4.91E+OO u TM 15 527400001 11/4/2020 Ce-144 -5.23E+OO 4.81E+OO l.55E+Ol u TM 15 527400001 11/4/2020 Co-57 5.37E-01 6.28E-01 2.12E+OO u TM 15 527400001 11/4/2020 Co-58 -7.65E-01 8.87E-01 2.38E+OO u TM 15 527400001 11/4/2020 Co-60 l.27E+OO 8.48E-01 2.75E+OO u TM 15 527400001 11/4/2020 Cr-51 7.50E+OO 7.56E+OO 2.51E+Ol u TM 15 527400001 11/4/2020 Cs-134 -l.81E+OO 8.75E-01 2.21E+OO u TM 15 527400001 11/4/2020 Cs-137 2.23E+OO 9.91E-01 2.21E+OO M TM 15 527400001 11/4/2020 Fe-59 -3.90E-01 l.83E+OO 5.78E+OO u TM 15 527400001 11/4/2020 1-131 -l.94E-02 3.85E-01 l.25E+OO UDL TM 15 527400001 11/4/2020 1-131 4.95E-01 2.14E+OO 7.14E+OO u TM 15 527400001 11/4/2020 K-40 1.62E+03 9.67E+Ol l.87E+Ol TM 15 527400001 11/4/2020 La-140 l.13E+OO 1.35E+OO 4.75E+OO u TM 15 527400001 11/4/2020 Mn-54 -1.75E-02 6.91E-01 l.99E+OO u TM 15 527400001 11/4/2020 Nb-95 -1.l IE-01 7.39E-01 2.38E+OO u TM 15 527400001 11/4/2020 Pb-212 -2.24E+OO 2.29E+OO 5.09E+OO u TM 15 527400001 11/4/2020 Pb-214 3.46E+OO 2.69E+OO 5.47E+OO u TM 15 527400001 11/4/2020 Ru-103 -l.46E+OO 8.27E-01 2.31E+OO u TM 15 527400001 11/4/2020 Ru-106 -8.88E-01 5.64E+OO l.83E+Ol u TM 15 527400001 11/4/2020 Sb-124 -7.51E-01 l.43E+OO 4.59E+OO u TM 15 527400001 11/4/2020 Sb-125 4.85E-02 1.67E+OO 5.53E+OO u TM 15 527400001 11/4/2020 Se-75 -l.88E-01 9.31E-01 3.IOE+OO u TM 15 527400001 11/4/2020 Th-228 -2.24E+OO 2.29E+OO 5.09E+OO u TM 15 527400001 11/4/2020 Zn-65 2.68E+OO 1.95E+OO 5.74E+OO u TM 15 527400001 11/4/2020 Zr-95 -9.54E-01 1.38E+OO 4.28E+OO u TM 15 529194001 12/2/2020 Ac-228 -l.28E+OO 3.39E+OO 8.65E+OO u TM 15 529194001 12/2/2020 Ag-108m -1.37E-03 4.23E-01 1.45E+OO u TM 15 529194001 12/2/2020 Ag-llOm 3.66E-01 7.77E-01 2.58E+OO u TM 15 529194001 12/2/2020 Ba-140 O.OOE+OO 7.00E+OO 9.49E+OO u TM 15 529194001 12/2/2020 Be-7 -2.27E+OO 4.20E+OO 1.39E+Ol u TM 15 529194001 12/2/2020 Bi-214 O.OOE+OO 2.80E+OO 3.42E+OO u TM 15 529194001 12/2/2020 Ce-141 -l.78E+OO l.07E+OO 2.84E+OO u TM 15 529194001 12/2/2020 Ce-144 l.62E+OO 3.44E+OO l.13E+Ol u TM 15 529194001 12/2/2020 Co-57 -4.61E-01 4.56E-01 1.42E+OO u TM 15 529194001 12/2/2020 Co-58 -3.38E-01 5.69E-01 l.81E+OO u TM 15 529194001 12/2/2020 Co-60 3.l 7E-01 6.81E-01 2.20E+OO u TM 15 529194001 12/2/2020 Cr-51 8.49E+OO 5.50E+OO l.58E+Ol u TM 15 529194001 12/2/2020 Cs-134 l.27E-01 5.92E-01 l.97E+OO u TM 15 529194001 12/2/2020 Cs-137 8.59E-01 8.93E-01 l.81E+OO u TM 15 529194001 12/2/2020 Fe-59 l.40E+OO 1.36E+OO 4.46E+OO u TM 15 529194001 12/2/2020 1-131 7.89E-03 l.82E-01 6.0IE-01 u TM 15 529194001 12/2/2020 1-131 6.85E-01 l.04E+OO 3.28E+OO u TM 15 529194001 12/2/2020 K-40 l.57E+03 7.88E+Ol l.65E+Ol TM 15 529194001 12/2/2020 La-140 2.91E-01 6.41E-01 2.23E+OO u 231

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/L) (pCi/ L) (pCi/L)

TM 15 529194001 12/2/2020 Mn-54 1.87E-01 5.80E-01 1.93E+OO u TM 15 529194001 12/2/2020 Nb-95 -5.30E-01 7.35E-01 1.88E+OO u TM 15 529194001 12/2/2020 Pb-212 O.OOE+OO 2.40E+OO 3.19E+OO u TM 15 529194001 12/2/2020 Pb-214 5.42E-02 1.61E+OO 4.16E+OO u TM 15 529194001 12/2/2020 Ru-103 -9.55E-04 5.55E-01 1.70E+OO u TM 15 529194001 12/2/2020 Ru-106 -2.99E+OO 4.60E+OO 1.48E+Ol u TM 15 529194001 12/2/2020 Sb-124 1.97E+OO 1.lOE+OO 3.85E+OO u TM 15 529194001 12/2/2020 Sb-125 1.62E+OO 1.36E+OO 4.64E+OO u TM 15 529194001 12/2/2020 Se-75 8.41E-01 7.24E-01 2.29E+OO u TM 15 529194001 12/2/2020 Th-228 O.OOE+OO 2.40E+OO 3.19E+OO u TM 15 529194001 12/2/2020 Zn-65 3.05E-01 1.34E+OO 4.36E+OO u TM 15 529194001 12/2/2020 Zr-95 5.97E-01 9.88E-01 3.32E+OO u 232

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/L) (pCi/ L) (pCi/ L)

WG 01 506970001 3/11/2020 Ac-228 5.55E+OO 4.92E+OO 8.71E+OO U WG 01 506970001 3/11/2020 Ag-108m 3.96E-Ol 5.25E-Ol l.79E+OO U WG 01 506970001 3/11/2020 Ag-llOm -l.08E+OO 8.52E-Ol 2.44E+OO U WG 01 506970001 3/11/2020 Ba-140 2.17E+OO 2.77E+OO 9.39E+OO U WG 01 506970001 3/11/2020 Be-7 -6.20E+OO 5.15E+OO l.58E+Ol U WG 01 506970001 3/11/2020 BETA 7.51E+OO l.37E+OO 2.36E+OO WG 01 506970001 3/11/2020 Bi-214 l.48E+Ol 3.23E+OO 3.40E+OO X(l)

WG 01 506970001 3/11/2020 Ce-141 4.20E-Ol l.20E+OO 3.57E+OO U WG 01 506970001 3/11/2020 Ce-144 -4.70E+OO 4.52E+OO l.37E+Ol U WG 01 506970001 3/11/2020 Co-57 3.76E-Ol 5.71E-Ol l.85E+OO U WG 01 506970001 3/11/2020 Co-58 -6.57E-Ol 5.96E-Ol l.76E+OO U WG 01 506970001 3/11/2020 Co-60 -6.00E-01 5.66E-Ol l.72E+OO U WG 01 506970001 3/11/2020 Cr-51 3.98E-Ol 5.46E+OO l.88E+Ol U WG 01 506970001 3/11/2020 Cs-134 -8.35E-Ol 6.91E-Ol l.74E+OO U WG 01 506970001 3/11/2020 Cs-137 l.64E-Ol 5.76E-Ol l.93E+OO U WG 01 506970001 3/11/2020 Fe-59 3.64E+OO l.40E+OO 4.lOE+OO U WG 01 506970001 3/11/2020 H-3 -6.43E+Ol l.68E+02 5.65E+02 U WG 01 506970001 3/11/2020 I-131 -l.03E-Ol 9.19E-Ol 3.12E+OO U WG 01 506970001 3/11/2020 K-40 -l.28E+Ol l.03E+Ol 2.96E+Ol U WG 01 506970001 3/11/2020 La-140 -l.54E+OO l.15E+OO 2.77E+OO U WG 01 506970001 3/11/2020 Mn-54 -5.42E-Ol 5.42E-Ol l.61E+OO U WG 01 506970001 3/11/2020 Nb-95 9.03E-Ol 5.90E-Ol l.96E+OO U WG 01 506970001 3/11/2020 Pb-212 l.51E+OO 2.20E+OO 3.82E+OO U WG 01 506970001 3/11/2020 Pb-214 l.45E+Ol 2.96E+OO 4.34E+OO WG 01 506970001 3/11/2020 Ru-103 3.63E-Ol 6.19E-OI 2.lOE+OO U WG 01 506970001 3/11/2020 Ru-106 3.75E-02 4.96E+OO l.65E+Ol U WG 01 506970001 3/11/2020 Sb-124 6.19E-Ol l.29E+OO 4.44E+OO U WG 01 506970001 3/11/2020 Sb-125 -2.20E-Ol l.63E+OO 5.47E+OO U WG 01 506970001 3/11/2020 Se-75 -5.59E-Ol 9.25E-Ol 2.80E+OO U WG 01 506970001 3/11/2020 Th-228 l.51E+OO 2.20E+OO 3.82E+OO U WG 01 506970001 3/11/2020 Zn-65 2.48E+OO l.47E+OO 4.44E+OO U WG 01 506970001 3/11/2020 Zr-95 -2.18E+OO l.13E+OO 2.89E+OO U WG 01 512891001 6/3/2020 Ac-228 -1.00E+Ol 4.82E+OO 7.69E+OO U WG 01 512891001 6/3/2020 Ag-108m -6.58E-Ol 8.28E-Ol l.63E+OO U WG 01 512891001 6/3/2020 Ag-1 lOm -9.34E-Ol 7.82E-Ol l.94E+OO U WG 01 512891001 6/3/2020 Ba-140 2.16E+OO 2.74E+OO 9.18E+OO U WG 01 512891001 6/3/2020 Be-7 -4.0IE+OO 4.53E+OO l.43E+Ol U WG 01 512891001 6/3/2020 BETA l.29E-02 1.IIE+OO 3.64E+OO U WG 01 512891001 6/3/2020 Bi-214 9.21E+OO 2.60E+OO 3.33E+OO X(l)

WG 01 512891001 6/3/2020 Ce-141 2.64E+OO l.47E+OO 3.40E+OO U WG 01 512891001 6/3/2020 Ce-144 1.14E+OO 3.81E+OO 1.23E+Ol U WG 01 512891001 6/3/2020 Co-57 6.I lE-01 5.45E-Ol l.73E+OO U WG 01 512891001 6/3/2020 Co-58 l.68E-Ol 5.08E-Ol l.66E+OO U WG 01 512891001 6/3/2020 Co-60 -5.46E-Ol 5.63E-Ol l.72E+OO U WG 01 512891001 6/3/2020 Cr-51 6.36E+OO 5.16E+OO l.73E+Ol U WG 01 512891001 6/3/2020 Cs-134 -2.69E-02 5.84E-Ol l.88E+OO U WG 01 512891001 6/3/2020 Cs-137 l.14E+OO 5.92E-Ol l.87E+OO U WG 01 512891001 6/3/2020 Fe-59 -3.03E+OO l.31E+OO 3.22E+OO U WG 01 512891001 6/3/2020 H-3 2.05E+02 l.74E+02 5.38E+02 U WG 01 512891001 6/3/2020 I-131 -7.62E-Ol 9.88E-Ol 3.22E+OO U 233

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/L) (pCi/ L) (pCi/L)

WG 01 512891001 6/3/2020 K-40 -1.27E+Ol l.13E+Ol 2.73E+Ol u WG 01 512891001 6/3/2020 La-140 3.97E-Ol 8.37E-01 2.83E+OO u WG 01 512891001 6/3/2020 Mn-54 -2.04E-Ol 4.99E-Ol l.56E+OO u WG 01 512891001 6/3/2020 Nb-95 -7.94E-Ol 6.15E-Ol l.79E+OO u WG 01 512891001 6/3/2020 Pb-212 l.98E+OO 2.30E+OO 4.27E+OO u WG 01 512891001 6/3/2020 Pb-214 9.96E+OO 2.87E+OO 3.90E+OO X(l)

WG 01 512891001 6/3/2020 Ru-103 -l.19E-Ol 5.90E-Ol l.74E+OO u WG 01 512891001 6/3/2020 Ru-106 -3.55E+OO 4.78E+OO l.SOE+Ol u WG 01 512891001 6/3/2020 Sb-124 2.07E+OO l.05E+OO 3.45E+OO u WG 01 512891001 6/3/2020 Sb-125 3.58E+OO 3.32E+OO 5.lOE+OO u WG 01 512891001 6/3/2020 Se-75 3.34E-02 7.06E-Ol 2.43E+OO u WG 01 512891001 6/3/2020 Th-228 l.98E+OO 2.30E+OO 4.27E+OO u WG 01 512891001 6/3/2020 Zn-65 3.58E+OO l.86E+OO 3.61E+OO u WG 01 512891001 6/3/2020 Zr-95 -1.83E-Ol 8.98E-Ol 2.87E+OO u WG 01 521449001 9/9/2020 Ac-228 -4.88E+OO 3.26E+OO 7.39E+OO u WG 01 521449001 9/9/2020 Ag-108m -6.58E-Ol 4.82E-Ol 1.46E+OO u WG 01 521449001 9/9/2020 Ag-llOm -3.64E-Ol 6.79E-01 2.09E+OO u WG 01 521449001 9/9/2020 Ba-140 2.72E+OO 3.58E+OO l.20E+Ol u WG 01 521449001 9/9/2020 Be-7 9.46E-02 4.87E+OO l.62E+Ol u WG 01 521449001 9/9/2020 BETA 4.66E+OO l.34E+OO 3.36E+OO WG 01 521449001 9/9/2020 Bi-214 O.OOE+OO 2.84E+OO 3.49E+OO u WG 01 521449001 9/9/2020 Ce-141 -4.66E-Ol l.27E+OO 3.69E+OO u WG 01 521449001 9/9/2020 Ce-144 -3.06E+OO 4.04E+OO l.26E+Ol u WG 01 521449001 9/9/2020 Co-57 -l.52E-Ol 5.30E-Ol l.70E+OO u WG 01 521449001 9/9/2020 Co-58 5.39E-02 5.46E-Ol l.77E+OO u WG 01 521449001 9/9/2020 Co-60 l.26E+OO 9.41E-Ol 2.09E+OO u WG 01 521449001 9/9/2020 Cr-51 -2.93E+OO l.94E+Ol 2.0IE+Ol u WG 01 521449001 9/9/2020 Cs-134 -3.12E-Ol 5.55E-Ol l.72E+OO u WG 01 521449001 9/9/2020 Cs-137 5.30E-Ol 5.47E-Ol l.81E+OO u WG 01 521449001 9/9/2020 Fe-59 -1.08E+OO l.15E+OO 3.62E+OO u WG 01 521449001 9/9/2020 H-3 2.44E+02 l.48E+02 4.54E+02 u WG 01 521449001 9/9/2020 I-131 -2.65E+OO l.60E+OO 4.75E+OO u WG 01 521449001 9/9/2020 K-40 l.84E+Ol l.63E+Ol 2.0IE+Ol u WG 01 521449001 9/9/2020 La-140 6.73E-02 l.23E+OO 3.56E+OO u WG 01 521449001 9/9/2020 Mn-54 9.41E-Ol 5.97E-Ol l.91E+OO u WG 01 521449001 9/9/2020 Nb-95 -8.49E-02 5.45E-Ol l.75E+OO u WG 01 521449001 9/9/2020 Pb-212 -6.44E-Ol l.81E+OO 4.09E+OO u WG 01 521449001 9/9/2020 Pb-214 3.19E+OO 3.07E+OO 4.94E+OO u WG 01 521449001 9/9/2020 Ru-103 -9.88E-Ol 6.61E-Ol l.96E+OO u WG 01 521449001 9/9/2020 Ru-106 2.38E-Ol 4.70E+OO l.54E+Ol u WG 01 521449001 9/9/2020 Sb-124 l.02E+OO l.31E+OO 4.47E+OO u WG 01 521449001 9/9/2020 Sb-125 -2.64E-Ol l.48E+OO 4.92E+OO u WG 01 521449001 9/9/2020 Se-75 -4.04E-Ol 7.27E-Ol 2.45E+OO u WG 01 521449001 9/9/2020 Th-228 -6.44E-Ol l.81E+OO 4.09E+OO u WG 01 521449001 9/9/2020 Zn-65 -1.0IE+OO l.15E+OO 3.64E+OO u WG 01 521449001 9/9/2020 Zr-95 l.15E+OO l.OIE+OO 3.31E+OO u WG 01 529195001 12/2/2020 Ac-228 -l.31E+OO 4.02E+OO 8.76E+OO u WG 01 529195001 12/2/2020 Ag-108m -7.69E-Ol 5.45E-Ol l.64E+OO u WG 01 529195001 12/2/2020 Ag-llOm -2.33E+OO 8.80E-01 l.94E+OO u 234

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/L) (pCi/ L) (pCi/ L)

WG 01 529195001 121212020 Ba-140 -4.27E+OO 3.06E+OO 8.97E+OO u WG 01 529195001 12/2/2020 Be-7 -2.18E+OO 4.44E+OO 1.43E+Ol u WG OJ 52919500J 12/2/2020 BET A 5.91E+OO l.48E+OO 3.57E+OO WG OJ 529J95001 12/2/2020 Bi-214 1.78E+Ol 2.2JE+OO 3.56E+OO X(l)

WG OJ 529195001 12/2/2020 Ce-141 1.15E+OO 9.84E-OJ 3.14E+OO u WG OJ 529195001 12/2/2020 Ce-144 3.62E+OO 3.80E+OO l.23E+Ol u WG 01 529195001 12/2/2020 Co-57 -2.65E-OJ 4.84E-Ol 1.55E+OO u WG OJ 529195001 J2/2/2020 Co-58 7.52E-Ol 6.05E-OJ 1.95E+OO u WG 01 529195001 12/2/2020 Co-60 l.05E+OO 7.14E-Ol 2.36E+OO u WG 01 529J 9500 J 12/2/2020 Cr-51 -6.55E+OO 5.22E+OO l.64E+Ol u WG OJ 52919500 I 12/2/2020 Cs-134 9.96E-Ol 6.52E-OJ 2.08E+OO u WG 01 529195001 12/2/2020 Cs-137 9.13E-OJ 6.64E-Ol 2.14E+OO u WG 01 529195001 J 2/2/2020 Fe-59 2.62E+OO l.38E+OO 4.47E+OO u WG 01 529195001 12/2/2020 H-3 -l.27E+Ol l.46E+02 4.83E+02 u WG OJ 52919500J 12/2/2020 1-131 l.88E+OO 2.51E+OO 3.39E+OO u WG 01 529195001 12/2/2020 K-40 -6.30E+OO l.29E+Ol 2.78E+Ol u WG OJ 52919500J J2/2/2020 La-140 l.07E+OO 1.06E+OO 3.52E+OO u WG 01 529195001 12/2/2020 Mn-54 -1.69E-Ol 5.46E-Ol l.83E+OO u WG OJ 52919500 J 12/2/2020 Nb-95 2.74E-Ol 6.48E-OJ 2.09E+OO u WG 01 529195001 12/2/2020 Pb-212 2.66E-OJ 1.90E+OO 3.86E+OO u WG 01 529195001 12/2/2020 Pb-214 O.OOE+OO 3.28E+OO 6.93E+OO u WG OJ 52919500 I 12/2/2020 Ru- I 03 l.69E+OO l.JOE+OO l.86E+OO u WG 01 529195001 12/2/2020 Ru-106 -4.61E-Ol 4.94E+OO l.59E+Ol u WG OJ 529J95001 12/2/2020 Sb-124 -1.JOE+OO l.78E+OO 4.92E+OO u WG OJ 529J9500J 12/2/2020 Sb-125 -1.79E+OO l.56E+OO 4.84£+00 u WG 01 529195001 12/2/2020 Se-75 -l.39E+OO 8. llE-OJ 2.17E+OO u WG 01 529J95001 12/2/2020 Th-228 2.66E-Ol 1.90E+OO 3.86E+OO u WG OJ 529195001 12/2/2020 Zn-65 l.16E+OO l.23E+OO 4.14E+OO u WG OJ 529195001 12/2/2020 Zr-95 8.69E-Ol l.06E+OO 3.43E+OO u WG 13 506970002 3/11/2020 Ac-228 -5.48E+OO 3.80E+OO 9.87E+OO u WG 13 506970002 3/1 J/2020 Ag-108m 4.75E-Ol 5.12E-Ol l.60E+OO u WG 13 506970002 3/11/2020 Ag-I !Om 4.63E-Ol 8.03E-OJ 2.66E+OO u WG 13 506970002 3/1 J/2020 Ba-140 -l.73E+OO 4.46E+OO 9.87E+OO u WG 13 506970002 3/11/2020 Be-7 O.OOE+OO 1.46E+OJ J .58E+Ol u WG 13 506970002 3/11/2020 BETA l.24E+OO 9.92E-Ol 2.96E+OO u WG 13 506970002 3/1 J/2020 Bi-214 8.24E+Ol 5.66E+OO 3.96E+OO X(l)

WG 13 506970002 3/1 J/2020 Ce-141 1.24E+OO 1.84E+OO 3.52£+00 u WG 13 506970002 3/11/2020 Ce-144 -2.36E+OO 4.55E+OO 1.45E+Ol u WG 13 506970002 3/11/2020 Co-57 8.27E-OJ 6.09E-Ol 1.94E+OO u WG 13 506970002 3/11/2020 Co-58 9. J8E-02 6.22E-Ol 2.03£+00 u WG 13 506970002 3/11/2020 Co-60 5.37E-Ol 7.00E-01 2.18E+OO u WG 13 506970002 3/11/2020 Cr-51 4.94E+OO 5.37E+OO l .85E+Ol u WG 13 506970002 3/11/2020 Cs-134 -2.02E-OJ 6.51E-Ol 2.07E+OO u WG 13 506970002 3/11/2020 Cs-137 5.38E-Ol 7.24E-Ol 2.20E+OO u WG 13 506970002 3/11/2020 Fe-59 -l.69E+OO l.39E+OO 3.87£+00 u WG 13 506970002 3/1 J/2020 H-3 -l.31E+02 l.57E+02 5.41E+02 u WG 13 506970002 3/11/2020 1-131 5.0lE-01 l.OIE+OO 3.46E+OO u WG 13 506970002 3/11/2020 K-40 2.57E+Ol J.27E+Ol l.74E+Ol M WG 13 506970002 3/11/2020 La-140 5.91E-Ol 9.79E-OJ 3.35E+OO u WG 13 506970002 3/11/2020 Mn-54 -8.74E-Ol 6.87E-Ol l.97E+OO u 235

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/L) (pCi/L) (pCi/ L)

WG 13. 506970002 3/11/2020 Nb-95 5.34E-01 8.37E-01 2.26E+OO u WG 13 506970002 3/11/2020 Pb-212 5.98E+OO 1.75E+OO 3.78E+OO X(l)

WG 13 506970002 3/11/2020 Pb-214 9.05E+Ol 5.91E+OO 4.25E+OO X(l)

WG 13 506970002 3/11/2020 Ru-103 -2.99E-01 6.41E-01 2.lOE+OO u WG 13 506970002 3/11/2020 Ru-106 -4.05E+OO 5.08E+OO 1.58E+Ol u WG 13 506970002 3/11/2020 Sb-124 9.59E-01 1.29E+OO 4.48E+OO u WG 13 506970002 3/11/2020 Sb-125 -9.22E-01 1.69E+OO 5.55E+OO u WG 13 506970002 3/11/2020 Se-75 -3.06E-02 9.30E-01 2.91E+OO u WG 13 506970002 3/11/2020 Th-228 5.98E+OO 1.75E+OO 3.78E+OO X(l)

WG 13 506970002 3/11/2020 Zn-65 -2.67E-01 l.39E+OO 3.82E+OO u WG 13 506970002 3/11/2020 Zr-95 -5.52E-01 1.12E+OO 3.51E+OO u WG 13 512891002 61312020 Ac-228 -2.18E+OO 3.60E+OO 9.09E+OO u WG 13 512891002 61312020 Ag-108m 1.20E+OO 6.89E-01 1.59E+OO u WG 13 512891002 6/3/2020 Ag-1 lOm 8.44E-01 7.94E-01 2.62E+OO u WG 13 512891002 61312020 Ba-140 2.18E+OO 2.96E+OO 1.0lE+Ol u WG 13 512891002 6/3/2020 Be-7 -1.97E+OO 5.07E+OO 1.58E+Ol u WG 13 512891002 6/3/2020 BETA 2.18E+OO l.13E+OO 3.23E+OO u WG 13 512891002 6/3/2020 Bi-214 4.85E+Ol 4.03E+OO 3.53E+OO X(l)

WG 13 512891002 6/3/2020 Ce-141 5. l lE-01 1.15E+OO 3.55E+OO u WG 13 512891002 6/3/2020 Ce-144 1.81E+OO 3.98E+OO l.36E+Ol u WG 13 512891002 6/3/2020 Co-57 -3.24E-01 5.18E-01 1.74E+OO u WG 13 512891002 6/3/2020 Co-58 -8.94E-01 6.16E-01 1.80E+OO u WG 13 512891002 6/3/2020 Co-60 -1.95E-01 6.31E-01 1.79E+OO u WG 13 512891002 61312020 Cr-51 -1.07E+Ol 6.05E+OO 1.71E+Ol u WG 13 512891002 6/3/2020 Cs-134 -1.46E-01 6.05E-01 1.97E+OO u WG 13 512891002 61312020 Cs-137 -9.61E-02 5.63E-01 1.87E+OO u WG 13 512891002 6/3/2020 Fe-59 -1.14E-01 1.1 lE+OO 3.55E+OO u WG 13 512891002 61312020 H-3 -1.67E+Ol 1.63E+02 5.39E+02 u WG 13 512891002 61312020 1-131 -4.18E-01 1.1 lE+OO 3.54E+OO u WG 13 512891002 6/3/2020 K-40 -2.09E+Ol 1.25E+Ol 2.67E+Ol u WG 13 512891002 61312020 La-140 -8.54E-01 1.03E+OO 3.18E+OO u WG 13 512891002 6/3/2020 Mn-54 -3.34E-01 5.97E-01 1.91E+OO u WG 13 512891002 6/3/2020 Nb-95 l.58E+OO 7.48E-01 2.lOE+OO u WG 13 512891002 6/3/2020 Pb-212 O.OOE+OO 2.40E+OO 3.50E+OO u WG 13 512891002 6/3/2020 Pb-214 5.26E+Ol 4.33E+OO 4.03E+OO X(l)

WG 13 512891002 6/3/2020 Ru-103 6.63E-02 6.33E-01 2.0lE+OO u WG 13 512891002 6/3/2020 Ru-106 2.51E+OO 4.94E+OO 1.67E+Ol u WG 13 512891002 6/3/2020 Sb-124 -4.63E-01 1.40E+OO 4.49E+OO u WG 13 512891002 6/3/2020 Sb-125 5.96E-01 1.86E+OO 5.34E+OO u WG 13 512891002 6/3/2020 Se-75 l.30E+OO 8.64E-01 2.75E+OO u WG 13 512891002 6/3/2020 Th-228 O.OOE+OO 2.40E+OO 3.50E+OO u WG 13 512891002 6/3/2020 Zn-65 8.27E-01 1.42E+OO 4.08E+OO u WG 13 512891002 61312020 Zr-95 7.23E-01 1.08E+OO 3.61E+OO u WG 13 521449002 9/9/2020 Ac-228 7.29E+OO 4.21E+OO 7.33E+OO u WG 13 521449002 91912020 Ag-108m -3.3 lE-01 3.83E-01 1.22E+OO u WG 13 521449002 9/9/2020 Ag-1 lOm -l.30E-01 7.38E-01 2.07E+OO u WG 13 521449002 91912020 Ba-140 O.OOE+OO 5.90E+OO 1.07E+Ol u WG 13 521449002 9/9/2020 Be-7 -3.33E+OO 3.98E+OO 1.26E+Ol u WG 13 521449002 9/9/2020 BETA 4.99E+OO l.39E+OO 3.43E+OO 236

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/L) (pCi/ L) (pCi/ L)

WG 13 521449002 9/9/2020 Bi-214 -9.0IE-01 l.67E+OO 3.52E+OO u WG 13 521449002 9/9/2020 Ce-141 -8.54E-01 9.0IE-01 2.76E+OO u WG 13 521449002 9/9/2020 Ce-144 3.15E+OO 2.90E+OO 9.26E+OO u WG 13 521449002 9/9/2020 Co-57 l.38E-01 4.04E-01 l.21E+OO u WG 13 521449002 9/9/2020 Co-58 -2.09E+OO 9.63E-01 l.23E+OO u WG 13 521449002 9/9/2020 Co-60 6.32E-02 4.44E-01 1.49E+OO u WG 13 521449002 9/9/2020 Cr-51 -2.03E+OO 4.40E+OO l.47E+Ol u WG 13 521449002 9/9/2020 Cs-134 4.42E-02 4.73E-01 l.53E+OO u WG 13 521449002 9/9/2020 Cs-137 -3.67E-01 4.51E-01 l.39E+OO u WG 13 521449002 9/9/2020 Fe-59 4.92E-01 9.47E-01 3.25E+OO u WG 13 521449002 9/9/2020 H-3 3.24E+Ol l.36E+02 4.42E+02 u WG 13 521449002 9/9/2020 1-131 2.94E+OO 2.03E+OO 3.94E+OO u WG 13 521449002 9/9/2020 K-40 O.OOE+OO l.26E+Ol l.35E+Ol u WG 13 521449002 9/9/2020 La-140 -l.14E+OO l.06E+OO 3.12E+OO u WG 13 521449002 9/9/2020 Mn-54 2.60E-01 4.60E-01 l.50E+OO u WG 13 521449002 9/9/2020 Nb-95 2.68E-02 4.93E-Ol l.59E+OO u WG 13 521449002 9/9/2020 Pb-212 -9.55E-01 2.05E+OO 4.92E+OO u WG 13 521449002 9/9/2020 Pb-214 2.56E-Ol 2.0IE+OO 3.62E+OO u WG 13 521449002 9/9/2020 Ru-103 -6.66E-01 5.19E-01 l.57E+OO u WG 13 521449002 9/9/2020 Ru-106 4.41E+OO 3.99E+OO l.32E+Ol u WG 13 521449002 9/9/2020 Sb-124 -4.36E-Ol l.20E+OO 3.82E+OO u WG 13 521449002 9/9/2020 Sb-125 l.48E+OO 1.27E+OO 4.22E+OO u WG 13 521449002 9/9/2020 Se-75 2.93E-02 5.63E-01 l.94E+OO u WG 13 521449002 9/9/2020 Th-228 -9.55E-01 2.05E+OO 4.92E+OO u WG 13 521449002 9/9/2020 Zn-65 -l.26E+OO 9.25E-01 2.74E+OO u WG 13 521449002 9/9/2020 Zr-95 l.23E+OO 8.77E-01 2.85E+OO u WG 13 529195002 12/2/2020 Ac-228 -3.80E+OO 4.47E+OO 9.98E+OO u WG 13 529195002 12/2/2020 Ag-108m 3.06E-01 5.86E-01 l.89E+OO u WG 13 529195002 12/2/2020 Ag-llOm 4.71E-01 9.38E-01 3.08E+OO u WG 13 529195002 12/2/2020 Ba-140 -2.49E+OO 3.43E+OO l.06E+Ol u WG 13 529195002 12/2/2020 Be-7 -9.03E-Ol 5.07E+OO l.71E+Ol u WG 13 529195002 12/2/2020 BETA 3.46E+OO 1.25E+OO 3.38E+OO M WG 13 529195002 12/2/2020 Bi-214 6.80E-02 2.69E+OO 5.65E+OO u WG 13 529195002 12/2/2020 Ce-141 -6.67E-01 l.05E+OO 3.52E+OO u WG 13 529195002 12/2/2020 Ce-144 3.0IE+OO 4.29E+OO l.34E+Ol u WG 13 529195002 12/2/2020 Co-57 9.46E-02 5.60E-01 l.76E+OO u WG 13 529195002 12/2/2020 Co-58 8.91E-Ol 6.50E-01 2.15E+OO u WG 13 529195002 12/2/2020 Co-60 l.70E-03 8.24E-01 2.70E+OO u WG 13 529195002 12/2/2020 Cr-51 7.32E-01 6.08E+OO l.99E+Ol u WG 13 529195002 12/2/2020 Cs-134 2.99E-Ol 6.81E-01 2.25E+OO u WG 13 529195002 12/2/2020 Cs-137 -3.31E-01 7.48E-01 2.41E+OO u WG 13 529195002 12/2/2020 Fe-59 -l.21E+OO 1.34E+OO 4.15E+OO u WG 13 529195002 12/2/2020 H-3 5.47E+Ol l.50E+02 4.87E+02 u WG 13 529195002 12/2/2020 1-131 -l.22E-01 1.20E+OO 3.86E+OO u WG 13 529195002 12/2/2020 K-40 O.OOE+OO 9.02E+OO l.87E+Ol u WG 13 529195002 12/2/2020 La-140 3.00E-01 1.21E+OO 3.45E+OO u WG 13 529195002 12/2/2020 Mn-54 -2.07E-Ol 6.49E-01 2.06E+OO u WG 13 529195002 12/2/2020 Nb-95 3.52E-02 6.72E-01 2.19E+OO u WG 13 529195002 12/2/2020 Pb-212 3.92E+OO 2.47E+OO 4.77E+OO u WG 13 529195002 12/2/2020 Pb-214 -2.44E+OO 2.35E+OO 5.53E+OO u 237

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/L) (pCi/L) (pCi/L)

WG 13 529195002 12/2/2020 Ru-103 7.99E-02 7.08E-01 2.12E+OO U WG 13 529195002 12/2/2020 Ru-106 6.77E+OO 6.31E+OO 2.llE+Ol U WG 13 529195002 12/2/2020 Sb-124 -l.14E+OO l.76E+OO 4.65E+OO U WG 13 529195002 12/2/2020 Sb-125 l.31E+OO l.74E+OO 5.61E+OO U WG 13 529195002 12/2/2020 Se-75 7.46E-02 8.26E-01 2.73E+OO U WG 13 529195002 12/2/2020 Th-228 3.92E+OO 2.47E+OO 4.77E+OO U WG 13 529195002 12/2/2020 Zn-65 6.49E-01 1.40E+OO 4.76E+OO U WG 13 529195002 12/2/2020 Zr-95 -1.51E-01 1.14E+OO 3.69E+OO U WG 14 506970003 3/11/2020 Ac-228 -1.0IE+OO 4.70E+OO 1.44E+Ol U WG 14 506970003 3/11/2020 Ag-108m -6.37E-01 8.21E-01 2.63E+OO U WG 14 506970003 3/11/2020 Ag-1 lOm 2.00E-01 1.28E+OO 4.37E+OO U WG 14 506970003 3/11/2020 Ba-140 -1.05E+OO 4.70E+OO 1.53E+Ol U DL WG 14 506970003 3/11/2020 Be-7 -3.39E-01 8.04E+OO 2.66E+Ol U WG 14 506970003 3/11/2020 BETA 6.05E+OO l.39E+OO 3.31E+OO WG 14 506970003 3/11/2020 Bi-214 2.58E+02 l.32E+Ol 6.52E+OO X(l)

WG 14 506970003 3/11/2020 Ce-141 -1.52E+OO 1.86E+OO 5.86E+OO U WG 14 506970003 3111/2020 Ce-144 5.62E+OO 6.91E+OO 2.25E+Ol U WG 14 506970003 3/11/2020 Co-57 8.75E-01 8.88E-01 2.90E+OO U WG 14 506970003 3/11/2020 Co-58 8.07E-01 1.09E+OO 3.18E+OO U WG 14 506970003 3/11/2020 Co-60 -1.54E-01 l.03E+OO 3.33E+OO U WG 14 506970003 3/11/2020 Cr-51 -9.54E+OO l.03E+Ol 2.94E+Ol U WG 14 506970003 3/11/2020 Cs-134 -6.25E-02 l.05E+OO 3.33E+OO U WG 14 506970003 3/11/2020 Cs-137 1.75E+OO 1.09E+OO 3.21E+OO U WG 14 506970003 3/11/2020 Fe-59 l.33E+OO l.78E+OO 6.06E+OO U WG 14 506970003 3/11/2020 H-3 l.11E+02 1.65E+02 5.21E+02 u WG 14 506970003 3/11/2020 1-131 -7.06E-01 1.45E+OO 4.79E+OO U WG 14 506970003 3/11/2020 K-40 O.OOE+OO 2.19E+Ol 2.99E+Ol U WG 14 506970003 3/11/2020 La-140 -9.91E-01 1.71E+OO 5.22E+OO U WG 14 506970003 3/11/2020 Mn-54 -2.25E-01 9.14E-Ol 3.07E+OO U WG 14 506970003 3/11/2020 Nb-95 1.29E+OO 1.20E+OO 3.49E+OO U WG 14 506970003 3/11/2020 Pb-212 3.33E+OO 2.56E+OO 6.75E+OO U WG 14 506970003 3111/2020 Pb-214 2.74E+02 1.46E+Ol 6.81E+OO X(l)

WG 14 506970003 3111/2020 Ru-103 2.50E-Ol 9.73E-01 2.91E+OO U WG 14 506970003 3/11/2020 Ru-106 9.74E+OO 8.29E+OO 2.72E+Ol U WG 14 506970003 3/11/2020 Sb-124 2.69E+OO 2.19E+OO 7.02E+OO U WG 14 506970003 3/11/2020 Sb-125 -1.49E+OO 2.56E+OO 8.32E+OO U WG 14 506970003 3/11/2020 Se-75 -l.17E+OO 1.47E+OO 4.39E+OO U WG 14 506970003 3/11/2020 Th-228 3.33E+OO 2.56E+OO 6.75E+OO U WG 14 506970003 3/11/2020 Zn-65 1.80E+OO 2.05E+OO 6.26E+OO U WG 14 506970003 3/11/2020 Zr-95 2.36E+OO 1.76E+OO 5.71E+OO U WG 14 512891003 6/3/2020 Ac-228 -2.65E+OO 3.38E+OO 8.08E+OO U WG 14 512891003 6/3/2020 Ag-108m -3.14E-02 4.65E-01 l.55E+OO U WG 14 512891003 6/3/2020 Ag-llOm l.35E+OO 8.04E-01 2.64E+OO U WG 14 512891003 6/3/2020 Ba-140 -2.25E+OO 2.67E+OO 8.40E+OO U WG 14 512891003 6/3/2020 Be-7 -9.46E+OO 5.12E+OO 1.46E+Ol U WG 14 512891003 6/3/2020 BETA 3.24E+OO l.llE+OO 3.06E+OO M WG 14 512891003 6/3/2020 Bi-214 1.69E+02 8.32E+OO 3.55E+OO X(l)

WG 14 512891003 6/3/2020 Ce-141 -4.45E+OO l.84E+OO 3.53E+OO U WG 14 512891003 6/3/2020 Ce-144 -2.81E+OO 4.04E+OO 1.29E+Ol U WG 14 512891003 6/3/2020 Co-57 -3.92E-Ol 5.25E-01 1.68E+OO U 238

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/L) (pCi/ L) (pCi/ L)

WG 14 512891003 61312020 Co-58 l.81E+OO 7.23E-01 1.90E+OO u WG 14 512891003 61312020 Co-60 -4.33E-01 5.63E-01 1.75E+OO u WG 14 512891003 61312020 Cr-5 I 6.04E+OO 5.62E+OO 1.89E+Ol u WG 14 512891003 61312020 Cs-134 2.45E-OI 6.20E-Ol 1.80E+OO u WG 14 512891003 61312020 Cs-13 7 -7.29E-Ol 9.07E-01 2.06E+OO u WG 14 512891003 61312020 Fe-59 -1.55E-01 1.23E+OO 3.59E+OO u WG 14 512891003 61312020 H-3 2.46E+02 1.83E+02 5.61E+02 u WG 14 512891003 61312020 1-I3 I -2.98E-01 1.0lE+OO 3.40E+OO u WG 14 512891003 61312020 K-40 l.37E+OO 1.04E+Ol 2.47E+Ol u WG 14 512891003 61312020 La- I 40 -2.71E-Ol 1.03E+OO 3.29E+OO u WG 14 512891003 61312020 Mn-54 -6.02E-02 5.37E-01 1.70E+OO u WG 14 512891003 61312020 Nb-95 4.72E-Ol 6.70E-01 1.94E+OO u WG 14 512891003 61312020 Pb-2I2 3.09E-01 1.90E+OO 3.40E+OO u WG 14 512891003 61312020 Pb-2 I 4 1.91E+02 9.42E+OO 3.98E+OO X(I)

WG 14 512891003 61312020 Ru- I 03 -1.53E+OO 6.77E-01 1.78E+OO u WG 14 512891003 61312020 Ru- I 06 -6.65E+OO 4.78E+OO 1.40E+Ol u WG 14 512891003 61312020 Sb- I 24 -6.48E-01 l.34E+OO 4.17E+OO u WG 14 512891003 61312020 Sb-I25 -1.53E+OO 1.58E+OO 5.05E+OO u WG 14 512891003 61312020 Se-75 -4.34E-01 8.24E-01 2.52E+OO u WG 14 512891003 61312020 Th-228 3.09E-OI 1.90E+OO 3.40E+OO u WG 14 512891003 61312020 Zn-65 -7.53E-01 1.21E+OO 3.40E+OO u WG 14 512891003 61312020 Zr-95 -1.63E+OO 1.05E+OO 2.94E+OO u WG 14 521449003 91912020 Ac-228 8.20E-01 2.91E+OO 6.36E+OO u WG 14 521449003 91912020 Ag-I08m -8.36E-02 3.90E-01 1.30E+OO u WG 14 521449003 91912020 Ag- I I Om 5.34E-01 6.35E-Ol 2.05E+OO u WG 14 521449003 91912020 Ba- I 40 -8.21E-01 4.02E+OO 9.45E+OO u WG 14 521449003 91912020 Be- 7 -3.67E+OO 4.35E+OO 1.23E+Ol u WG 14 521449003 91912020 BETA 1.53E+OO 8.21E-01 2.24E+OO u WG 14 521449003 91912020 Bi-2I4 6.59E+Ol 4.00E+OO 2.81E+OO X(I)

WG 14 521449003 91912020 Ce-I4I -3.12E+OO 1.25E+OO 3. lOE+OO u WG 14 521449003 91912020 Ce-I44 O.OOE+OO 4.61E+OO 1.04E+Ol u WG 14 521449003 91912020 Co-57 -4.74E-01 4.43E-01 l.37E+OO u WG 14 521449003 91912020 Co-58 4.63E-01 4.83E-01 1.42E+OO u WG 14 521449003 91912020 Co-60 -1.96E-01 4.47E-01 1.44E+OO u WG 14 521449003 91912020 Cr-5 I 1.48E+OO 4.63E+OO 1.59E+OI u WG 14 521449003 91912020 Cs-134 7.44E-01 7.42E-Ol 1.59E+OO u WG 14 521449003 91912020 Cs-13 7 -6.30E-01 5.42E-01 1.44E+OO u WG 14 521449003 91912020 Fe-59 -7.50E-02 1.0lE+OO 3.41E+OO u WG 14 521449003 91912020 H-3 1.22E+02 1.43E+02 4.55E+02 u WG 14 521449003 91912020 1-I3I 7.95E-01 1.18E+OO 4.04E+OO u WG 14 521449003 9/912020 K-40 -7.71E+OO 1.02E+Ol 2.42E+Ol u WG 14 521449003 91912020 La-140 -l.29E+OO 1.07E+OO 3.14E+OO u WG 14 521449003 91912020 Mn-54 -1.92E-01 4.SlE-01 l.34E+OO u WG 14 521449003 91912020 Nb-95 7.13E-Ol 1.19E+OO 1.47E+OO u WG 14 521449003 91912020 Pb-2I2 -1.80E+OO 1.33E+OO 3.22E+OO u WG 14 521449003 91912020 Pb-2I4 7.30E+Ol 4.42E+OO 3.03E+OO X(I)

WG 14 521449003 91912020 Ru- I 03 -6.47E-02 5.55E-01 1.65E+OO u WG 14 521449003 91912020 Ru- I 06 -1.00E+OO 4.0lE+OO 1.30E+Ol u WG 14 521449003 91912020 Sb-I24 -1.67E-01 1.05E+OO 3.37E+OO u WG 14 521449003 91912020 Sb-I25 -8.41E-02 1.24E+OO 4.18E+OO u 239

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/L) (pCi/L) (pCi/L)

WG 14 521449003 91912020 Se-75 5.54E-01 7.02E-01 2.20E+OO u WG 14 521449003 91912020 Th-228 -1.80E+OO 1.33E+OO 3.22E+OO u WG 14 521449003 91912020 Zn-65 8.llE-02 1.05E+OO 3.12E+OO u WG 14 521449003 91912020 Zr-95 3.57E-01 8.43E-01 2.76E+OO u WG 14 529195003 12/2/2020 Ac-228 5.75E+OO 3.15E+OO 9.99E+OO u WG 14 529195003 12/2/2020 Ag-108m O.OOE+OO O.OOE+OO 1.91E+OO u WG 14 529195003 12/2/2020 Ag-1 lOm -3.43E-01 9.53E-01 3.13E+OO u WG 14 529195003 12/2/2020 Ba-140 7.34E+OO 4.12E+OO 1.15E+Ol u WG 14 529195003 12/2/2020 Be-7 1.77E+OO 6.52E+OO 1.89E+Ol u WG 14 529195003 12/2/2020 BETA 3.llE+OO 1.24E+OO 3.42E+OO u WG 14 529195003 12/2/2020 Bi-214 2.53E+02 1.24E+Ol 4.59E+OO X(l)

WG 14 529195003 12/2/2020 Ce-141 2.33E-01 1.36E+OO 3.91E+OO u WG 14 529195003 12/2/2020 Ce-144 -8.76E-01 4.55E+OO 1.42E+Ol u WG 14 529195003 12/2/2020 Co-57 6.64E-02 5.63E-01 1.78E+OO u WG 14 529195003 12/2/2020 Co-58 2.91E-01 7.72E-01 2.31E+OO u WG 14 529195003 12/2/2020 Co-60 -2.56E-01 7.56E-01 2.40E+OO u WG 14 529195003 12/2/2020 Cr-51 -7.78E+OO 6.38E+OO l.99E+Ol u WG 14 529195003 12/2/2020 Cs-134 1.51E+OO 8.47E-01 2.72E+OO u WG 14 529195003 12/2/2020 Cs-137 9.73E-OI 8.04E-OI 2.42E+OO u WG 14 529195003 12/2/2020 Fe-59 -3.08E+OO 1.65E+OO 4.47E+OO u WG 14 529195003 12/2/2020 H-3 -2.52E+Ol 1.45E+02 4.80E+02 u WG 14 529195003 12/2/2020 I-131 -9.53E-01 1.24E+OO 3.96E+OO u WG 14 529195003 12/2/2020 K-40 -9.78E+OO 1.33E+Ol 2.84E+Ol u WG 14 529195003 12/2/2020 La-140 1.13E+OO 1.31E+OO 4.45E+OO u WG 14 529195003 12/2/2020 Mn-54 -5.53E-01 7.87E-01 2.22E+OO u WG 14 529195003 12/2/2020 Nb-95 1.45E+OO 1.28E+OO 2.65E+OO u WG 14 529195003 12/2/2020 Pb-212 O.OOE+OO 2.66E+OO 3.78E+OO u WG 14 529195003 12/2/2020 Pb-214 2.70E+02 l.29E+Ol 5.00E+OO X(I)

WG 14 529195003 12/2/2020 Ru-103 -1.26E+OO 8.93E-01 2.31E+OO u WG 14 529195003 12/2/2020 Ru-106 -4.20E+OO 6.25E+OO 1.92E+OI u WG 14 529195003 12/2/2020 Sb-124 -1.73E+OO 1.66E+OO 5.12E+OO u WG 14 529195003 12/2/2020 Sb-125 -2.79E+OO 2.00E+OO 5.98E+OO u WG 14 529195003 12/2/2020 Se-75 4.06E-01 8.69E-01 2.92E+OO u WG 14 529195003 12/2/2020 Th-228 O.OOE+OO 2.66E+OO 3.78E+OO u WG 14 529195003 12/2/2020 Zn-65 -2.46E+OO 1.93E+OO 4.94E+OO u WG 14 529195003 12/2/2020 Zr-95 9.76E-01 1.21E+OO 4.1 IE+OO u 240

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/L) (pCi/L) (pCi/ L) ws 01 501556001 1/13/2020 Ac-228 -1.05E+Ol 3.96E+OO 6.57E+OO u ws 01 501556001 1/13/2020 Ag-108m 3.61E-01 3.99E-01 1.34E+OO u ws 01 501556001 1/13/2020 Ag-llOm -8.44E-02 6.57E-01 2.09E+OO u ws 01 501556001 1/13/2020 Ba-140 -2.54E+OO 2.99E+OO 7.44E+OO u ws 01 501556001 1/13/2020 Be-7 -5.68E+OO 4.22E+OO 1.27E+Ol u ws 01 501556001 1/13/2020 Bi-214 9.41E-01 2.16E+OO 3.83E+OO u ws 01 501556001 1/13/2020 Ce-141 -3.46E+OO 1.42E+OO 2.62E+OO u ws 01 501556001 1/13/2020 Ce-144 5.30E+OO 3.33E+OO 1.02E+Ol u ws 01 501556001 1/13/2020 Co-57 -6.54E-02 4.00E-01 1.28E+OO u ws 01 501556001 1/13/2020 Co-58 1.13E+OO 5.74E-01 1.78E+OO u ws 01 501556001 1/13/2020 Co-60 2.39E-01 4.76E-01 1.62E+OO u ws 01 501556001 1/13/2020 Cr-51 -3.32E+OO 4.16E+OO 1.36E+Ol u ws 01 501556001 1/13/2020 Cs-134 -2.69E-01 5.26E-01 1.64E+OO u ws 01 501556001 1/13/2020 Cs-137 -2.41E-Ol 4.77E-01 1.51E+OO u ws 01 501556001 1/13/2020 Fe-59 2.32E+OO 2.48E+OO 3.14E+OO u ws 01 501556001 1/13/2020 1-131 1.47E-01 8. l IE-01 2.75E+OO u ws 01 501556001 1/13/2020 K-40 3.23E+02 2.43E+Ol 1.56E+Ol ws 01 501556001 1/13/2020 La-140 -1.59E-02 8.15E-01 2.68E+OO u ws 01 501556001 1/13/2020 Mn-54 -8.38E-02 4.73E-01 1.50E+OO u ws 01 501556001 1/13/2020 Nb-95 -5.40E-01 6.06E-01 1.62E+OO u ws 01 501556001 1/13/2020 Pb-212 8.89E-01 1.89E+OO 5.50E+OO u ws 01 501556001 1/13/2020 Pb-214 -2.20E+OO 1.85E+OO 3.74E+OO u ws 01 501556001 1/13/2020 Ru-103 -8.57E-01 5.53E-01 1.62E+OO u ws 01 501556001 1/13/2020 Ru-106 6.02E+OO 4.39E+OO 1.43E+Ol u ws 01 501556001 1/13/2020 Sb-124 -l.31E+OO l.09E+OO 3.lOE+OO u ws 01 501556001 1/13/2020 Sb-125 1.64E+OO l.29E+OO 4.28E+OO u ws 01 501556001 1/13/2020 Se-75 -1.03E+OO 6.52E-01 2.00E+OO u ws 01 501556001 1/13/2020 Th-228 8.89E-01 l.89E+OO 5.50E+OO u ws 01 501556001 1/13/2020 Zn-65 9.84E-01 1.lOE+OO 3.76E+OO u ws 01 501556001 1/13/2020 Zr-95 -2.12E+OO 9.63E-01 2.34E+OO u ws 01 504485001 2/12/2020 Ac-228 3.54E+OO 3.34E+OO 5.99E+OO u ws 01 504485001 2/12/2020 Ag-108m 1.94E-01 3.58E-01 1.22E+OO u ws 01 504485001 2/12/2020 Ag-1 lOm 4.89E-Ol 5.36E-01 l.76E+OO u ws 01 504485001 2/12/2020 Ba-140 -2.76E-01 2.15E+OO 7.15E+OO u ws 01 504485001 2/12/2020 Be-7 -6.52E-01 3.20E+OO 1.07E+Ol u ws 01 504485001 2/12/2020 Bi-214 -1.51E+OO 1.75E+OO 3.18E+OO u ws 01 504485001 2/12/2020 Ce-141 -2.0IE+OO 8.78E-01 2.27E+OO u ws 01 504485001 2/12/2020 Ce-144 -2.81E+OO 2.70E+OO 8.31E+OO u ws 01 504485001 2/12/2020 Co-57 7.25E-01 3.77E-01 l.14E+OO u ws 01 504485001 2/12/2020 Co-58 -3.54E-01 4.15E-01 1.27E+OO u ws 01 504485001 2/12/2020 Co-60 l.16E+OO 4.96E-01 1.57E+OO u ws 01 504485001 2/12/2020 Cr-51 8.70E+OO 6.48E+OO 1.28E+Ol u ws 01 504485001 2/12/2020 Cs-134 7.24E-01 4.45E-01 1.44E+OO u ws 01 504485001 2/12/2020 Cs-137 1.95E-03 4.54E-01 1.34E+OO u ws 01 504485001 2/12/2020 Fe-59 4.44E-01 9.16E-01 2.95E+OO u ws 01 504485001 2/12/2020 1-131 -l.03E-01 6.97E-01 2.37E+OO u ws 01 504485001 2/12/2020 K-40 3.20E+02 2.24E+Ol l.31E+Ol ws 01 504485001 2/12/2020 La-140 4.49E-01 6.71E-01 2.05E+OO u ws 01 504485001 2/12/2020 Mn-54 6.98E-01 4.34E-01 1.39E+OO u ws 01 504485001 2/12/2020 Nb-95 7.25E-01 6.98E-01 1.32E+OO u 241

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/L) (pCi/ L) (pCi/L) ws 01 504485001 2/12/2020 Pb-212 1.07E+OO 1.53E+OO 2.92E+OO u ws 01 504485001 2/12/2020 Pb-214 -4.54E-01 1.43E+OO 3.llE+OO u ws 01 504485001 211212020 Ru-103 1.04E-01 4.46E-01 1.35E+OO u ws 01 504485001 2/12/2020 Ru-106 1.37E+OO 3.45E+OO 1.15E+Ol u ws 01 504485001 2/12/2020 Sb-124 -8.95E-02 9.17E-01 3.0lE+OO u ws 01 504485001 2/12/2020 Sb-125 -9.16E-01 1.08E+OO 3.09E+OO u ws 01 504485001 2/12/2020 Se-75 -5.56E-01 5.95E-01 1.78E+OO u ws 01 504485001 2/12/2020 Th-228 1.07E+OO 1.53E+OO 2.92E+OO u ws 01 504485001 2/12/2020 Zn-65 -1.00E+OO 1.02E+OO 3.0lE+OO u ws 01 504485001 2/12/2020 Zr-95 -7.86E-01 7.61E-01 2.30E+OO u ws 01 507593001 3/18/2020 Ac-228 3.99E+OO 5.34E+OO 8.32E+OO u ws 01 507593001 3/18/2020 Ag-108m 6.23E-01 4.48E-01 1.49E+OO u ws 01 507593001 3/18/2020 Ag-llOm -1.54E-01 6.51E-Ol 2.05E+OO u ws 01 507593001 3/18/2020 Ba-140 -2.36E+OO 2.54E+OO 7.87E+OO u ws 01 507593001 3/18/2020 Be-7 4.19E+OO 4.43E+OO 1.48E+Ol u ws 01 507593001 3/18/2020 Bi-214 3.50E+OO 1.93E+OO 4.26E+OO u ws 01 507593001 3/18/2020 Ce-141 9.53E-01 9.00E-01 2.85E+OO u ws 01 507593001 3/18/2020 Ce-144 -2.44E-01 3.41E+OO 1.09E+Ol u ws 01 507593001 3/18/2020 Co-57 7.77E-01 4.75E-01 1.47E+OO u ws 01 507593001 3/18/2020 Co-58 7.79E-01 6.29E-01 1.61E+OO u ws 01 507593001 3/18/2020 Co-60 8.37E-01 6.79E-01 2.30E+OO u ws 01 507593001 3/18/2020 Cr-51 7.47E+OO 4.92E+OO 1.63E+Ol u ws 01 507593001 3/18/2020 Cs-134 1.15E+OO 6.43E-01 1.87E+OO u ws 01 507593001 3/18/2020 Cs-137 -2.66E-01 5.25E-01 1.66E+OO u ws 01 507593001 3/18/2020 Fe-59 3.14E-02 1.IOE+OO 3.74E+OO u ws 01 507593001 3/18/2020 I-131 1.74E+OO 1.0lE+OO 3.28E+OO u ws 01 507593001 3/18/2020 K-40 3.40E+02 2.80E+Ol 1.60E+Ol ws 01 507593001 3/18/2020 La-140 2.61E+OO 1.77E+OO 2.79E+OO u ws 01 507593001 3/18/2020 Mn-54 1.05E+OO 5.68E-01 1.80E+OO u ws 01 507593001 3/18/2020 Nb-95 4.02E-01 4.87E-01 1.61E+OO u ws 01 507593001 3/18/2020 Pb-212 -4.04E+OO 2.IOE+OO 5.77E+OO u ws 01 507593001 3/18/2020 Pb-214 4.00E+OO 2.78E+OO 4.42E+OO u ws 01 507593001 3/18/2020 Ru-103 -1.0lE+OO 6.07E-01 1.74E+OO u ws 01 507593001 3/18/2020 Ru-106 -3.90E+OO 4.77E+OO 1.48E+Ol u ws 01 507593001 3/18/2020 Sb-124 7.50E-01 l.23E+OO 4.15E+OO u ws 01 507593001 3/18/2020 Sb-125 3.79E+OO 1.59E+OO 4.82E+OO u ws 01 507593001 3/18/2020 Se-75 -3.00E-01 6.24E-01 2.IOE+OO u ws 01 507593001 3/18/2020 Tb-228 -4.04E+OO 2.IOE+OO 5.77E+OO u ws 01 507593001 3/18/2020 Zn-65 2.95E+OO l.31E+OO 4.19E+OO u ws 01 507593001 3/18/2020 Zr-95 7.83E-01 9.46E-01 3.12E+OO u ws 01 510624001 3/18/2020 H-3 2.45E+02 1.23E+02 3.67E+02 u ws 01 509885001 4/15/2020 Ac-228 7.19E+OO 3.44E+OO 8.25E+OO u ws 01 509885001 4/15/2020 Ag-108m -3.41E-01 4.72E-01 1.53E+OO u ws 01 509885001 4/15/2020 Ag-llOm -2.59E-01 7.39E-01 2.32E+OO u ws 01 509885001 4/15/2020 Ba-140 9.46E-01 2.71E+OO 9.06E+OO u ws 01 509885001 4/15/2020 Be-7 7.14E+OO 4.79E+OO 1.57E+Ol u ws 01 509885001 4/15/2020 Bi-214 2.55E+OO 2.98E+OO 3.41E+OO u 242

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/L) (pCi/ L) (pCi/ L) ws 01 509885001 4115/2020 Ce-141 4.16E-01 l.93E+OO 3.46E+OO u ws 01 509885001 4/15/2020 Ce-144 l.99E+OO 3.96E+OO l.28E+Ol u ws 01 509885001 4/15/2020 Co-57 9.67E-01 5.82E-01 l.79E+OO u ws 01 509885001 4/15/2020 Co-58 -1.98E-02 5.46E-01 l.75E+OO u ws 01 509885001 4/15/2020 Co-60 4.07E-01 5.69E-01 l.95E+OO u ws 01 509885001 4115/2020 Cr-51 -1.53E+Ol 8.59E+OO l.79E+Ol u ws 01 509885001 4115/2020 Cs-134 -l.75E+OO l.08E+OO l.89E+OO u ws 01 509885001 4/15/2020 Cs-137 l.48E+OO l.02E+OO 1.84E+OO u ws 01 509885001 4/15/2020 Fe-59 7.16E-Ol 1.IOE+OO 3.79E+OO u ws 01 509885001 4/15/2020 I-131 -5.48E-02 9.49E-01 3.21E+OO u ws 01 509885001 4/15/2020 K-40 3.39E+02 2.87E+Ol l.62E+Ol ws 01 509885001 4/15/2020 La-140 -l.65E+OO 9.96E-01 2.66E+OO u ws 01 509885001 4/15/2020 Mn-54 -5.80E-Ol 5.77E-01 l.72E+OO u ws 01 509885001 4115/2020 Nb-95 2.62E-Ol 5.39E-Ol l.77E+OO u ws 01 509885001 4/15/2020 Pb-212 3.66E+OO 2.93E+OO 4.24E+OO u ws 01 509885001 4/15/2020 Pb-214 O.OOE+OO 3.51E+OO 4.70E+OO u ws 01 509885001 4/15/2020 Ru-103 8.78E-02 5.61E-Ol l.87E+OO u ws 01 509885001 4/15/2020 Ru-106 -6.66E-01 4.81E+OO 1.57E+Ol u ws 01 509885001 4/15/2020 Sb-124 3.82E+OO l.69E+OO 5.07E+OO u ws 01 509885001 4115/2020 Sb-125 -9.51E-01 1.39E+OO 4.50E+OO u ws 01 509885001 4/15/2020 Se-75 3.55E-01 7.43E-01 2.56E+OO u ws 01 509885001 4/15/2020 Th-228 3.66E+OO 2.93E+OO 4.24E+OO u ws 01 509885001 4/15/2020 Zn-65 -1.38E+OO 1.19E+OO 3.66E+OO u ws 01 509885001 4/15/2020 Zr-95 6.26E-01 9.60E-01 3.16E+OO u ws 01 511584001 5/11/2020 Ac-228 -1.04E+Ol 5.70E+OO 8.41E+OO u ws 01 511584001 5/11/2020 Ag-108m 2.89E-01 4.76E-01 l.54E+OO u ws 01 511584001 5/11/2020 Ag-llOm -2.47E-01 7.71E-01 2.48E+OO u ws 01 511584001 5/1112020 Ba-140 l.64E+OO 3.48E+OO 1.19E+Ol u ws 01 511584001 5/1112020 Be-7 8.38E+OO 5.35E+OO l.67E+Ol u ws 01 511584001 5/11/2020 Bi-214 -2.25E+OO 2.24E+OO 4.46E+OO u ws 01 511584001 5/11/2020 Ce-141 2.38E+OO l.26E+OO 3.61E+OO u ws 01 511584001 5/1112020 Ce-144 -2.86E+OO 3.77E+OO l.25E+Ol u ws 01 511584001 5/11/2020 Co-57 O.OOE+OO 7.42E-Ol l.61E+OO u ws 01 511584001 5111/2020 Co-58 l.28E+OO 6.88E-01 l.99E+OO u ws 01 511584001 5/11/2020 Co-60 -l.40E-01 5.87E-01 1.94E+OO u ws 01 511584001 5/1112020 Cr-51 -5.94E+OO 5.72E+OO l.76E+Ol u ws 01 511584001 5/1112020 Cs-134 5.55E-Ol 7.27E-Ol 2.02E+OO u ws 01 511584001 5/1112020 Cs-137 6.73E-02 5.76E-01 l.93E+OO u ws 01 511584001 5/1112020 Fe-59 -2.67E+OO 1.49E+OO 3.94E+OO u ws 01 511584001 5/1112020 I-131 1.46E-01 l.42E+OO 4.61E+OO u ws 01 511584001 5/11/2020 K-40 3.61E+02 2.55E+Ol l.63E+Ol ws 01 511584001 5/11/2020 La-140 -4.51E-01 l.29E+OO 4.15E+OO u ws 01 511584001 5/1112020 Mn-54 3.79E-Ol 5.67E-Ol l.88E+OO u ws 01 511584001 5/1112020 Nb-95 1.35E+OO 6.74E-01 2.12E+OO u ws 01 511584001 5/11/2020 Pb-212 -5.68E+OO 2.66E+OO 4.21E+OO u ws 01 511584001 5/1112020 Pb-214 2.65E-02 2.44E+OO 4.26E+OO u ws 01 511584001 5/1112020 Ru-103 -3.09E-01 7.49E-01 2.06E+OO u ws 01 511584001 5/1112020 Ru-106 -3.84E-Ol 4.86E+OO 1.63E+Ol u ws 01 511584001 511112020 Sb-124 -1.87E+OO l.50E+OO 4.34E+OO u ws 01 511584001 5/1112020 Sb-125 1.20E+OO l.51E+OO 4.87E+OO u 243

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/L) (pCi/ L) (pCi/ L) ws 01 511584001 5/11/2020 Se-75 3.34E-01 7.76E-01 2.57E+OO u ws 01 511584001 5/11/2020 Th-228 -5.68E+OO 2.66E+OO 4.21E+OO u ws 01 511584001 5/11/2020 Zn-65 -7.60E-01 1.24E+OO 3.81E+OO u ws 01 511584001 5/11/2020 Zr-95 2.87E+OO 1.93E+OO 3.67E+OO u ws 01 514167001 6/16/2020 Ac-228 -2.20E+OO 3.37E+OO 8.24E+OO u ws 01 514167001 6/16/2020 Ag-108m 4.42E-01 5.34E-01 1.55E+OO u ws 01 514167001 6/16/2020 Ag-llOm -1.95E-01 8.24E-Ol 2.35E+OO u ws 01 514167001 6/16/2020 Ba-140 7.16E-01 2.64E+OO 8.43E+OO u ws 01 514167001 6/16/2020 Be-7 5.85E+OO 5.76E+OO 1.49E+Ol u ws 01 514167001 6/16/2020 Bi-214 O.OOE+OO 2.42E+OO 3.66E+OO u ws 01 514167001 6/16/2020 Ce-141 -1.09E+OO 1.0lE+OO 3.28E+OO u ws 01 514167001 6/16/2020 Ce-144 1.42E-02 3.63E+OO 1.24E+Ol u ws 01 514167001 6/16/2020 Co-57 4.30E-02 4.91E-01 1.69E+OO u ws 01 514167001 6/16/2020 Co-58 4.18E-01 5.09E-01 1.71E+OO u ws 01 514167001 6/16/2020 Co-60 1.07E+OO 5.96E-01 1.98E+OO u ws 01 514167001 6/16/2020 Cr-51 -5.80E+OO 5.34E+OO 1.65E+Ol u ws 01 514167001 6/16/2020 Cs-134 5.30E-01 5.61E-01 1.88E+OO u ws 01 514167001 6/16/2020 Cs-137 1.09E+OO 5.86E-01 1.89E+OO u ws 01 514167001 6/16/2020 Fe-59 l.15E+OO 1.33E+OO 3.88E+OO u ws 01 514167001 6/16/2020 1-131 -1.91E-01 9.36E-01 3.03E+OO u ws 01 514167001 6/16/2020 K-40 3.26E+02 2.80E+Ol 1.94E+Ol ws 01 514167001 6/16/2020 La-140 6.02E-01 8.84E-01 3.0lE+OO u ws 01 514167001 6/16/2020 Mn-54 -8.03E-01 5.40E-01 1.57E+OO u ws 01 514167001 6/16/2020 Nb-95 5.29E-01 7.42E-01 1.76E+OO u ws 01 514167001 6/16/2020 Pb-212 8.45E+OO 2.68E+OO 3.26E+OO ws 01 514167001 6/16/2020 Pb-214 3.78E+OO 2.99E+OO 4.69E+OO u ws 01 514167001 6/16/2020 Ru-103 -1.llE+OO 6.27E-01 1.70E+OO u ws 01 514167001 6/16/2020 Ru-106 2.90E+OO 4.66E+OO 1.58E+Ol u ws 01 514167001 6/16/2020 Sb-124 -7.04E-01 l.17E+OO 3.67E+OO u ws 01 514167001 6/16/2020 Sb-125 -4.86E-01 1.58E+OO 4.46E+OO u ws 01 514167001 6/16/2020 Se-75 9.22E-Ol 7.53E-01 2.45E+OO u ws 01 514167001 6/16/2020 Th-228 8.45E+OO 2.68E+OO 3.26E+OO ws 01 514167001 6/16/2020 Zn-65 -5.69E-01 1.35E+OO 3.71E+OO u ws 01 514167001 6/16/2020 Zr-95 1.35E-01 9.14E-01 3.06E+OO u ws 01 517017001 6/16/2020 H-3 -5.57E+Ol 1.34E+02 4.46E+02 u ws 01 516195001 7/13/2020 Ac-228 3.12E+OO 4.00E+OO 8.82E+OO u ws 01 516195001 7/13/2020 Ag-108m -6.65E-01 5.33E-01 1.62E+OO u ws 01 516195001 711312020 Ag-llOm -6.63E-01 8.74E-01 2.82E+OO u ws 01 516195001 7/13/2020 Ba-140 4.95E+OO 3.42E+OO l.12E+Ol u ws 01 516195001 7113/2020 Be-7 -2.05E+OO 5.14E+OO 1.67E+Ol u ws 01 516195001 7113/2020 Bi-214 -6.02E-01 2.00E+OO 4.65E+OO u ws 01 516195001 7/13/2020 Ce-141 9.30E-01 1.06E+OO 3.43E+OO u ws 01 516195001 7/13/2020 Ce-144 -2.66E+OO 3.94E+OO 1.25E+Ol u ws 01 516195001 7113/2020 Co-57 7.59E-01 5.43E-01 1.73E+OO u ws 01 516195001 7/13/2020 Co-58 2.07E-01 7.03E-01 2.25E+OO u ws 01 516195001 711312020 Co-60 O.OOE+OO 1.42E+OO 2.41E+OO u ws 01 516195001 7/13/2020 Cr-51 -1.40E+OO 5.45E+OO 1.84E+Ol u 244

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/L) (pCi/ L) (pCi/ L) ws 01 516195001 7113/2020 Cs-134 5.47E-Ol 6.71E-Ol 2.18E+OO U ws 01 516195001 7/13/2020 Cs-137 8.51E-Ol 6.91E-Ol 2.24E+OO u ws 01 516195001 7113/2020 Fe-59 -2.09E-Ol l.53E+OO 5.03E+OO u ws 01 516195001 7/13/2020 1-131 -2.89E-Ol 1.1 IE+OO 3.71E+OO u ws 01 516195001 7/13/2020 K-40 3.27E+02 2.93E+Ol 2.02E+Ol ws 01 516195001 7/13/2020 La-140 -8.75E-Ol l.05E+OO 3.06E+OO u ws 01 516195001 7/13/2020 Mn-54 -3.40E-Ol 5.63E-Ol l.85E+OO u ws 01 516195001 7/13/2020 Nb-95 -7.29E-Ol 6.93E-Ol 2.03E+OO u ws 01 516195001 7113/2020 Pb-212 O.OOE+OO 3.03E+OO 4.52E+OO u ws 01 516195001 7/13/2020 Pb-214 -3.07E+OO 2.00E+OO 4.61E+OO u ws 01 516195001 7/13/2020 Ru-103 -5.88E-Ol 6.53E-Ol 2.04E+OO u ws 01 516195001 7/13/2020 Ru-106 4.08E+OO 5.39E+OO l.77E+Ol u ws 01 516195001 7/13/2020 Sb-124 -1.80E+OO l.51E+OO 4.47E+OO u ws 01 516195001 7/13/2020 Sb-125 -1.45E+OO l.59E+OO 5.03E+OO u ws 01 516195001 7/13/2020 Se-75 1.59E+OO 9.0IE-01 2.70E+OO u ws 01 516195001 7/13/2020 Th-228 O.OOE+OO 3.03E+OO 4.52E+OO u ws 01 516195001 7/13/2020 Zn-65 -1.86E+OO l.47E+OO 4.38E+OO u ws 01 516195001 7/13/2020 Zr-95 4.02E-Ol l.15E+OO 3.71E+OO u ws 01 518708001 8/10/2020 Ac-228 6.72E+OO 5.61E+OO l.15E+Ol u ws 01 518708001 8/10/2020 Ag-108m -6.37E-Ol 6.25E-Ol l.94E+OO u ws 01 518708001 8/10/2020 Ag-I 10m 2.07E-Ol 9.15E-Ol 3.13E+OO u ws 01 518708001 8/10/2020 Ba-140 3.46E+OO 3.90E+OO l.31E+Ol u ws 01 518708001 8/10/2020 Be-7 -1.62E+OO 5.64E+OO 1.84E+Ol u ws 01 518708001 8/10/2020 Bi-214 O.OOE+OO 3.02E+OO 4.75E+OO u ws 01 518708001 8/10/2020 Ce-141 8.30E-Ol l.87E+OO 3.90E+OO u ws 01 518708001 8/10/2020 Ce-144 -3.20E+OO 4.72E+OO 1.50E+Ol u ws 01 518708001 8/10/2020 Co-57 7.48E-Ol 6.50E-Ol 2.12E+OO u ws 01 518708001 8/10/2020 Co-58 -l.51E+OO 8.62E-Ol 2.17E+OO u ws 01 518708001 8/10/2020 Co-60 2.88E+OO 1.45E+OO 3.21E+OO u ws 01 518708001 8/10/2020 Cr-51 -7.75E+OO 6.88E+OO 2.18E+Ol u ws 01 518708001 8/10/2020 Cs-134 -5.87E-Ol l.05E+OO 2.57E+OO u ws 01 518708001 8/10/2020 Cs-137 -6.79E-Ol 8.42E-Ol 2.55E+OO u ws 01 518708001 8/10/2020 Fe-59 2.04E+OO l.71E+OO 5.85E+OO u ws 01 518708001 8/10/2020 1-131 -1.74E-Ol l.24E+OO 4.17E+OO u ws 01 518708001 8/10/2020 K-40 3.71E+02 3.28E+Ol 2.56E+Ol ws 01 518708001 8/10/2020 La-140 -l.37E+OO l.39E+OO 3.91E+OO u ws 01 518708001 8/10/2020 Mn-54 -5.92E-Ol 7.32E-Ol 2.34E+OO u ws 01 518708001 8/10/2020 Nb-95 1.15E+OO 7.98E-Ol 2.61E+OO u ws 01 518708001 8/10/2020 Pb-212 1.89E+OO 2.34E+OO 4.29E+OO u ws 01 518708001 8/10/2020 Pb-214 5.86E+OO 3.26E+OO 6.61E+OO u ws 01 518708001 8/10/2020 Ru-103 2.80E-Ol 7.54E-Ol 2.53E+OO u ws 01 518708001 8/10/2020 Ru-106 -1.60E+Ol 7.83E+OO l.95E+Ol u ws 01 518708001 8/10/2020 Sb-124 7.49E-02 l.71E+OO 5.05E+OO u ws 01 518708001 8/10/2020 Sb-125 4.61E-Ol l.80E+OO 6.09E+OO u ws 01 518708001 8/10/2020 Se-75 9.86E-Ol l.OIE+OO 3.20E+OO u ws 01 518708001 8/10/2020 Th-228 l.89E+OO 2.34E+OO 4.29E+OO u ws 01 518708001 8/10/2020 Zn-65 -2.39E+OO l.64E+OO 4.57E+OO u ws 01 518708001 8/10/2020 Zr-95 l.20E-Ol l.33E+OO 4.27E+OO u ws 01 522263001 9/14/2020 Ac-228 -5.55E+OO 4.02E+OO 7.04E+OO u 245

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/L) (pCi/ L) (pCi/ L) ws 01 522263001 9/14/2020 Ag-108m 3.86E-02 3.82E-01 1.26E+OO u ws 01 522263001 9/14/2020 Ag-llOm -9.78E-01 6.71E-01 l.91E+OO u ws 01 522263001 9/14/2020 Ba-140 5.45E+OO 3.49E+OO 1.12E+Ol u ws 01 522263001 9/14/2020 Be-7 6.82E-01 4.23E+OO l.40E+Ol u ws 01 522263001 9/14/2020 Bi-214 -1.97E+OO l.78E+OO 3.57E+OO u ws 01 522263001 9/14/2020 Ce-141 -2.24E+OO l.14E+OO 3.32E+OO u ws 01 522263001 9/14/2020 Ce-144 l.14E+OO 3.25E+OO l.IOE+Ol u ws 01 522263001 9/14/2020 Co-57 3.13E-01 4.28E-01 l.45E+OO u ws 01 522263001 9/14/2020 Co-58 -1.57E-02 4.92E-01 l.59E+OO u ws 01 522263001 9/14/2020 Co-60 -1.46E-02 5.05E-01 l.60E+OO u ws 01 522263001 9/14/2020 Cr-51 1.44E+OO 5.08E+OO l.70E+Ol u ws 01 522263001 9/14/2020 Cs-134 4.61E-01 4.90E-01 1.54E+OO u ws 01 522263001 9/14/2020 Cs-137 O.OOE+OO 6.21E-01 1.37E+OO u ws 01 522263001 9/14/2020 Fe-59 -1.13E-OI l.04E+OO 3.32E+OO u ws 01 522263001 9/14/2020 I-131 7.29E-01 l.54E+OO 5.14E+OO u ws 01 522263001 9/14/2020 K-40 3.43E+02 2.67E+Ol l.46E+Ol ws 01 522263001 9/14/2020 La-140 -5.66E-01 l.07E+OO 3.50E+OO u ws 01 522263001 9/14/2020 Mn-54 -3.55E-OI 4.55E-01 1.41E+OO u ws 01 522263001 9/14/2020 Nb-95 -9.42E-01 8.0IE-01 l.64E+OO u ws 01 522263001 9/14/2020 Pb-212 1.07E-01 1.92E+OO 2.76E+OO u ws 01 522263001 9/14/2020 Pb-214 -7.29E-01 l.85E+OO 3.60E+OO u ws 01 522263001 9/14/2020 Ru-103 -7.09E-01 5.63E-01 l.71E+OO u ws 01 522263001 9/14/2020 Ru-106 -2.88E+OO 3.96E+OO l.24E+Ol u ws 01 522263001 9/14/2020 Sb-124 7.74E-02 1.09E+OO 3.70E+OO u ws 01 522263001 9/14/2020 Sb-125 -2.34E-01 1.23E+OO 4.03E+OO u ws 01 522263001 9/14/2020 Se-75 -3.67E-01 6.43E-01 2.llE+OO u ws 01 522263001 9/14/2020 Th-228 1.07E-01 l.92E+OO 2.76E+OO u ws 01 522263001 9/14/2020 Zn-65 1.47E-01 9.03E-01 2.91E+OO u ws 01 522263001 9/14/2020 Zr-95 -l.58E+OO 9.40E-01 2.61E+OO u ws 01 526424001 9/14/2020 H-3 3.53E+Ol 1.65E+02 5.37E+02 u ws 01 524955001 10/15/2020 Ac-228 4.08E+OO 4.32E+OO 5.64E+OO u ws 01 524955001 10/15/2020 Ag-108m -8.92E-01 4.36E-01 l.17E+OO u ws 01 524955001 10/15/2020 Ag-llOm -l.43E+OO 9.60E-01 2.00E+OO u ws 01 524955001 10/15/2020 Ba-140 4.75E+OO 3.22E+OO 1.0IE+Ol u ws 01 524955001 10/15/2020 Be-7 -7.56E-01 4.09E+OO l.32E+Ol u ws 01 524955001 10/15/2020 Bi-214 2.56E+OO 2.36E+OO 2.67E+OO u ws 01 524955001 10/15/2020 Ce-141 -4.76E+OO 1.73E+OO 2.77E+OO u ws 01 524955001 10/15/2020 Ce-144 2.83E+OO 3.lOE+OO 9.79E+OO u ws 01 524955001 10/15/2020 Co-57 3.94E-01 3.93E-01 l.24E+OO u ws 01 524955001 10/15/2020 Co-58 -3.36E-01 4.73E-01 1.52E+OO u ws 01 524955001 10/15/2020 Co-60 -l.35E-OI 4.76E-01 1.59E+OO u ws 01 524955001 10/15/2020 Cr-51 -7.39E+OO 4.99E+OO l.51E+Ol u ws 01 524955001 10/15/2020 Cs-134 5.73E-01 5.18E-01 l.73E+OO u ws 01 524955001 10/15/2020 Cs-137 3.15E-01 4.49E-01 l.53E+OO u ws 01 524955001 10/15/2020 Fe-59 -l.09E+OO l.06E+OO 3.21E+OO u ws 01 524955001 10/15/2020 I-131 8.53E-01 l.25E+OO 4.15E+OO u ws 01 524955001 10/15/2020 K-40 3.10E+02 2.27E+Ol l.38E+Ol ws 01 524955001 10/15/2020 La-140 -5.20E-01 9.78E-01 3.15E+OO u ws 01 524955001 10/15/2020 Mn-54 -7.07E-01 4.73E-01 l.40E+OO u 246

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/L) (pCi/ L) (pCi/L) ws 01 524955001 10/15/2020 Nb-95 2.80E-01 4.81E-Ol l.62E+OO u ws 01 524955001 10/15/2020 Pb-212 5.52E+OO 2.03E+OO 2.69E+OO ws 01 524955001 10/15/2020 Pb-214 3.57E+OO 2.23E+OO 3.83E+OO u ws 01 524955001 10/15/2020 Ru-103 -8.46E-01 5.75E-01 l.67E+OO u ws 01 524955001 10/15/2020 Ru-106 -2.94E+OO 4.15E+OO l.27E+Ol u ws 01 524955001 10/15/2020 Sb-124 6.05E-03 1.12E+OO 3.72E+OO u ws 01 524955001 l 0/15/2020 Sb-125 l.44E+OO l.25E+OO 4.05E+OO u ws 01 524955001 10/15/2020 Se-75 9.07E-02 5.80E-01 l.96E+OO u ws 01 524955001 10/15/2020 Th-228 5.52E+OO 2.03E+OO 2.69E+OO ws 01 524955001 10/15/2020 Zn-65 2.70E+OO l.08E+OO 3.27E+OO u ws 01 524955001 l 0/15/2020 Zr-95 l.30E-Ol 8.41E-01 2.83E+OO u ws 01 528806001 11117/2020 Ac-228 1.1 IE+OO 4.28E+OO 6.IOE+OO u ws 01 528806001 11 /17 /2020 Ag-108m -5.98E-02 3.23E-01 l.08E+OO u ws 01 528806001 11117/2020 Ag-llOm -l.l IE-02 5.75E-Ol l.83E+OO u ws 01 528806001 11117/2020 Ba-140 4.45E+OO 2.98E+OO 9.65E+OO u ws 01 528806001 11/17/2020 Be-7 4.15E+OO 3.74E+OO l.24E+Ol u ws 01 528806001 11/17/2020 Bi-214 l.57E+OO 1.94E+OO 2.53E+OO u ws 01 528806001 11/17/2020 Ce-141 -l.54E+OO 8.85E-01 2.50E+OO u ws 01 528806001 11/17/2020 Ce-144 l.48E+OO 2.67E+OO 8.60E+OO u ws 01 528806001 11117/2020 Co-57 4.16E-Ol 3.57E-01 l.l3E+OO u ws 01 528806001 11/17/2020 Co-58 7.40E-02 4.13E-Ol 1.33E+OO u ws 01 528806001 11 /17/2020 Co-60 7. llE-01 4.49E-Ol l.49E+OO u ws 01 528806001 11/17/2020 Cr-51 4.67E+OO 4.20E+OO l.41E+Ol u ws 01 528806001 11/17/2020 Cs-134 l.77E-Ol 4.30E-01 1.40E+OO u ws 01 528806001 11 /17/2020 Cs-13 7 -l.14E-Ol 4.1 IE-01 l.26E+OO u ws 01 528806001 11/17/2020 Fe-59 -4.41E-01 9.29E-01 3.06E+OO u ws 01 528806001 11/17/2020 I-131 8.63E-01 1.25E+OO 4.25E+OO u ws 01 528806001 11/17/2020 K-40 3.50E+02 2.33E+Ol 1.13E+Ol ws 01 528806001 11/17/2020 La-140 -7.49E-01 1.05E+OO 3.27E+OO u ws 01 528806001 11/17/2020 Mn-54 -2.78E-01 4.25E-01 1.31E+OO u ws 01 528806001 11/17/2020 Nb-95 l.54E-01 4.IOE-01 l.33E+OO u ws 01 528806001 11/17/2020 Pb-212 l.13E+OO l.65E+OO 2.l7E+OO u ws 01 528806001 11/17/2020 Pb-214 -l.02E+OO 1.44E+OO 3.08E+OO u ws 01 528806001 11 /17/2020 Ru- I 03 -5.74E-01 4.75E-01 l.46E+OO u ws 01 528806001 11 /1 7/2020 Ru-106 5.04E+OO 3.57E+OO l.16E+Ol u ws 01 528806001 11117/2020 Sb-124 -7.17E-02 1.06E+OO 3.45E+OO u ws 01 528806001 11/17/2020 Sb-125 4.60E-02 1.02E+OO 3.41E+OO u ws 01 528806001 11117/2020 Se-75 -4.96E-01 5.24E-01 1.73E+OO u ws 01 528806001 11/17/2020 Th-228 l.13E+OO 1.65E+OO 2.l7E+OO u ws 01 528806001 11/17/2020 Zn-65 l.93E+OO 9.56E-01 2.55E+OO u ws 01 528806001 11/17/2020 Zr-95 -7.75E-01 8.l8E-Ol 2.48E+OO u ws 01 530337001 12/9/2020 Ac-228 -l.81E+OO 3.37E+OO 7.30E+OO u ws 01 530337001 12/9/2020 Ag-108m 2.69E-02 4.21E-Ol l.41E+OO u ws 01 530337001 12/9/2020 Ag-llOm 6.lOE-01 6.91E-Ol 2.37E+OO u ws 01 530337001 12/9/2020 Ba-140 -4.51E+OO 3.56E+OO 1.06E+Ol u ws 01 530337001 12/9/2020 Be-7 -6.53E+OO 4.65E+OO l.39E+Ol u ws 01 530337001 12/9/2020 Bi-214 2.69E+OO 2.36E+OO 3.34E+OO u ws 01 530337001 12/9/2020 Ce-141 -3.18E+OO l.67E+OO 3.17E+OO u ws 01 530337001 12/9/2020 Ce-144 -l.41E+OO 3.18E+OO l.03E+Ol u 247

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/L) (pCi/L) (pCi/ L) ws 01 530337001 12/9/2020 Co-57 -4.67E-01 4.17E-01 1.29E+OO u ws 01 530337001 12/9/2020 Co-58 -2.46E-01 5.89E-01 1.83E+OO u ws 01 530337001 12/9/2020 Co-60 7.42E-01 6.22E-01 2.08E+OO u ws 01 530337001 12/9/2020 Cr-51 -3.81E+OO 5.07E+OO 1.67E+Ol u ws 01 530337001 12/9/2020 Cs-134 4.47E-01 5.55E-01 1.80E+OO u ws 01 530337001 12/9/2020 Cs-137 -3.16E-01 5.57E-01 1.75E+OO u ws 01 530337001 12/9/2020 Fe-59 9.72E-01 1.26E+OO 4.26E+OO u ws 01 530337001 12/9/2020 I-131 -1.95E+OO 1.52E+OO 4.71E+OO u ws 01 530337001 12/9/2020 K-40 3.58E+02 2.50E+Ol 1.32E+Ol ws 01 530337001 12/9/2020 La-140 -4.04E+OO 2.90E+OO 3.49E+OO u ws 01 530337001 12/9/2020 Mn-54 1.93E-01 5.42E-01 1.74E+OO u ws 01 530337001 12/9/2020 Nb-95 6.32E-01 5.77E-01 1.87E+OO u ws 01 530337001 12/9/2020 Pb-212 -1.68E+OO 1.51E+OO 3.40E+OO u ws 01 530337001 12/9/2020 Pb-214 -3.66E+OO 2.07E+OO 4.1 lE+OO u ws 01 530337001 12/9/2020 Ru-103 -7.51E-01 6.05E-01 1.84E+OO u ws 01 530337001 12/9/2020 Ru-106 -6.55E-01 4.57E+OO 1.48E+Ol u ws 01 530337001 12/9/2020 Sb-124 -1.95E+OO 1.66E+OO 4.70E+OO u ws 01 530337001 12/9/2020 Sb-125 -1.SOE+OO 1.35E+OO 4.20E+OO u ws 01 530337001 12/9/2020 Se-75 -4.08E-01 7.0lE-01 2.13E+OO u ws 01 530337001 12/9/2020 Th-228 -1.68E+OO 1.51E+OO 3.40E+OO u ws 01 530337001 12/9/2020 Zn-65 -4.02E-02 1.20E+OO 3.50E+OO u ws 01 530337001 12/9/2020 Zr-95 -4.15E-01 1.lOE+OO 3.45E+OO u ws 01 533258001 12/9/2020 H-3 -9.09E+Ol 9.97E+Ol 3.38E+02 u ws 10 511584004 5/13/2020 Ac-228 3.43E+OO 3.97E+OO 5.58E+OO u ws 10 511584004 5/13/2020 Ag-108m 3.06E-01 3.79E-01 1.26E+OO u ws 10 511584004 5/13/2020 Ag-11 Om -1.lOE+OO 6. l lE-01 1.73E+OO u ws 10 511584004 5/13/2020 Ba-140 6.51E-01 2.38E+OO 7.82E+OO u ws 10 511584004 5/13/2020 Be-7 -6.04E+OO 3.91E+OO 1.14E+Ol u ws 10 511584004 5/13/2020 Bi-214 -1.02E+OO 1.85E+OO 3.52E+OO u ws 10 511584004 5/13/2020 Ce-141 -1.58E+OO 9.77E-01 2.53E+OO u ws 10 511584004 5/13/2020 Ce-144 1.03E-01 2.80E+OO 8.92E+OO u ws 10 511584004 5/13/2020 Co-57 -6.97E-02 3.70E-01 1.18E+OO u ws 10 511584004 5/13/2020 Co-58 -2.76E-01 4.05E-01 1.33E+OO u ws 10 511584004 5/13/2020 Co-60 1.18E+OO 5.54E-01 1.74E+OO u ws 10 511584004 5/13/2020 Cr-51 -3.19E+OO 4.07E+OO 1.32E+Ol u ws 10 511584004 5/13/2020 Cs-134 -5.72E-01 4.51E-01 1.40E+OO u ws 10 511584004 5/13/2020 Cs-137 6.75E-01 4.86E-01 1.55E+OO u ws 10 511584004 5/13/2020 Fe-59 3.08E-01 9.24E-01 3.lOE+OO u ws 10 511584004 5/13/2020 I-131 -l.3 IE-01 9.03E-01 3.00E+OO u ws 10 511584004 5/13/2020 K-40 1.14E+02 1.55E+Ol 1.23E+Ol ws 10 511584004 5/13/2020 La-140 -1.31E+OO 9.48E-01 2.20E+OO u ws 10 511584004 5/13/2020 Mn-54 -6.44E-01 4.98E-01 1.33E+OO u ws 10 511584004 5/13/2020 Nb-95 -6.32E-02 4.76E-01 1.50E+OO u ws 10 511584004 5/13/2020 Pb-212 2.48E-01 1.42E+OO 3.13E+OO u ws 10 511584004 5/13/2020 Pb-214 1.1 lE-01 1.92E+OO 3.39E+OO u ws 10 511584004 5/13/2020 Ru-103 2.56E-02 5.21E-01 1.53E+OO u ws 10 511584004 5/13/2020 Ru-106 1.59E+OO 3.78E+OO 1.23E+Ol u ws 10 511584004 5/13/2020 Sb-124 7.12E-01 1.02E+OO 3.36E+OO u ws 10 511584004 5/13/2020 Sb-125 -1.39E+OO 1.20E+OO 3.71E+OO u 248

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/L) (pCi/ L) (pCi/L) ws 10 511584004 5/13/2020 Se-75 -5.58E-01 5.75E-01 1.87E+OO u ws IO 511584004 5113/2020 Th-228 2.48E-01 1.42E+OO 3.13E+OO u ws 10 511584004 5/13/2020 Zn-65 3.15E-02 8.58E-01 2.85E+OO u ws 10 511584004 5113/2020 Zr-95 -1.14E+OO 8.80E-01 2.52E+OO u ws 10 528806004 11/19/2020 Ac-228 O.OOE+OO 4.51E+OO 6.61E+OO u ws 10 528806004 11119/2020 Ag-108m -2.29E-01 4.18E-Ol l.33E+OO u ws 10 528806004 11/19/2020 Ag-llOm 6.92E-01 7.15E-01 2.40E+OO u ws 10 528806004 11119/2020 Ba-140 -4.05E+OO 3.31E+OO 9.75E+OO u ws 10 528806004 11119/2020 Be-7 -1.47E+OO 4.57E+OO 1.46E+Ol u ws 10 528806004 11/19/2020 Bi-214 -2.74E+OO 2.40E+OO 3.93E+OO u ws 10 528806004 11/19/2020 Ce-141 -2.53E+OO 1.52E+OO 2.54E+OO u ws 10 528806004 11/19/2020 Ce-144 -2.55E+OO 2.77E+OO 8.34E+OO u ws 10 528806004 11/19/2020 Co-57 -3.41E-02 3.46E-01 1.09E+OO u ws 10 528806004 11/19/2020 Co-58 -3.59E-01 5.48E-01 1.78E+OO u ws 10 528806004 11/19/2020 Co-60 4.07E-01 6.36E-01 l.85E+OO u ws 10 528806004 11/19/2020 Cr-51 -5.04E+OO 4.61E+OO 1.44E+Ol u ws 10 528806004 11/19/2020 Cs-134 -1.IOE-01 5.51E-Ol 1.84E+OO u ws 10 528806004 11/19/2020 Cs-137 -l.32E-01 5.08E-01 1.71E+OO u ws 10 528806004 11/19/2020 Fe-59 -1.60E+OO 1.25E+OO 3.71E+OO u ws 10 528806004 11/19/2020 I-131 1.07E+OO 1.27E+OO 4.18E+OO u ws 10 528806004 11/19/2020 K-40 2.26E+02 2.05E+Ol 1.88E+Ol ws 10 528806004 11/19/2020 La-140 1.53E+OO 1.66E+OO 3.65E+OO u ws IO 528806004 11/19/2020 Mn-54 -1.41E+OO 6.61E-01 1.49E+OO u ws IO 528806004 11/19/2020 Nb-95 1.06E+OO 5.85E-01 1.89E+OO u ws IO 528806004 11/19/2020 Pb-212 2.15E+OO 1.98E+OO 3.04E+OO u ws IO 528806004 11/19/2020 Pb-214 3.14E+OO l.95E+OO 3.67E+OO u ws 10 528806004 11119/2020 Ru-103 -4.22E-01 5.49E-01 1.70E+OO u ws 10 528806004 11/19/2020 Ru-106 8.85E-01 4.49E+OO 1.44E+Ol u ws IO 528806004 11 /19/2020 Sb-124 -l.33E+OO 1.15E+OO 3.42E+OO u ws 10 528806004 11/19/2020 Sb-125 -l.69E+OO 1.27E+OO 3.79E+OO u ws 10 528806004 11/19/2020 Se-75 -4.65E-01 5.43E-01 1.75E+OO u ws 10 528806004 11/19/2020 Th-228 2.15E+OO 1.98E+OO 3.04E+OO u ws 10 528806004 11119/2020 Zn-65 1.72E+OO 1.22E+OO 3.98E+OO u ws 10 528806004 11119/2020 Zr-95 l.03E-01 9.26E-01 3.13E+OO u ws 51 501556002 1/14/2020 Ac-228 5.18E+OO 5.39E+OO 8.24E+OO u ws 51 501556002 1114/2020 Ag-108m 3.24E-02 4.58E-01 l.38E+OO u ws 51 501556002 1/14/2020 Ag-llOm -l.32E+OO 7.70E-01 2.21E+OO u ws 51 501556002 1114/2020 Ba-140 -l.35E+OO 2.29E+OO 7.29E+OO u ws 51 501556002 1114/2020 Be-7 5.93E+OO 4.28E+OO 1.41E+Ol u ws 51 501556002 1114/2020 Bi-214 l.49E+OO 2.91E+OO 3.34E+OO u ws 51 501556002 1/14/2020 Ce-141 -1.21E+OO l.36E+OO 2.72E+OO u ws 51 501556002 1114/2020 Ce-144 -4.41E-01 3.27E+OO 1.07E+Ol u ws 51 501556002 1114/2020 Co-57 -2.20E-01 4.20E-01 l.36E+OO u ws 51 501556002 1114/2020 Co-58 4.30E-03 5.25E-01 1.66E+OO u ws 51 501556002 1/14/2020 Co-60 5.43E-01 5.85E-01 1.96E+OO u ws 51 501556002 1114/2020 Cr-51 3.86E+OO 4.46E+OO 1.52E+Ol u ws 51 501556002 1114/2020 Cs-134 -1.04E+OO 6.20E-01 1.65E+OO u ws 51 501556002 1114/2020 Cs-137 2.84E-01 5.47E-01 1.79E+OO u ws 51 501556002 1114/2020 Fe-59 1.09E+OO 1.04E+OO 3.51E+OO u 249

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/L) (pCi/ L) (pCi/ L) ws 51 501556002 1/14/2020 1-131 1.87E-01 7.80E-01 2.65E+OO u ws 51 501556002 1/14/2020 K-40 3.21E+02 2.46E+Ol 1.83E+01 ws 51 501556002 1/14/2020 La-140 -2.52E+OO 1.0IE+OO 1.98E+OO u ws 51 501556002 1/14/2020 Mn-54 -1.49E-01 4.72E-01 1.58E+OO u ws 51 501556002 1/14/2020 Nb-95 2.14E-01 5.89E-01 1.70E+OO u ws 51 501556002 1/14/2020 Pb-212 9.93E-01 2.04E+OO 3.51E+OO u ws 51 501556002 1/14/2020 Pb-214 7.46E-01 2.79E+OO 4.16E+OO u ws 51 501556002 1/14/2020 Ru-103 5.59E-01 5.70E-01 1.71E+OO u ws 51 501556002 1/14/2020 Ru-106 8.65E+OO 4.98E+OO 1.58E+Ol u ws 51 501556002 1/14/2020 Sb-124 -6.33E-01 1.28E+OO 4.16E+OO u ws 51 501556002 1/14/2020 Sb-125 -1.72E+OO 1.33E+OO 4.05E+OO u ws 51 501556002 1/14/2020 Se-75 -1.31E+OO 7.82E-01 2.13E+OO u ws 51 501556002 1/14/2020 Th-228 9.93E-01 2.04E+OO 3.51E+OO u ws 51 501556002 1/14/2020 Zn-65 1.16E-01 1.07E+OO 3.57E+OO u ws 51 501556002 1114/2020 Zr-95 -1.38E+OO 1.11E+OO 2.76E+OO u ws 51 504485002 2/11/2020 Ac-228 -9.60E+OO 6.21E+OO 1.03E+Ol u ws 51 504485002 2/1112020 Ag- I 08m -2.75E-01 6.0IE-01 2.0IE+OO u ws 51 504485002 2/11/2020 Ag-llOm -7.01E-01 9.46E-01 2.87E+OO u ws 51 504485002 2/1112020 Ba-140 1.47E+OO 3.49E+OO 1.18E+01 u ws 51 504485002 2/11/2020 Be-7 4.87E-01 5.86E+OO 1.99E+01 u ws 51 504485002 2/1112020 Bi-214 -5.75E-01 3.21E+OO 5.91E+OO u ws 51 504485002 2/1112020 Ce-141 -2.43E+OO 1.83E+OO 3.93E+OO u ws 51 504485002 2/11/2020 Ce-144 -5.01E-01 4.69E+OO 1.44E+01 u ws 51 504485002 2/11/2020 Co-57 -1.67E+OO 9.29E-01 1.84E+OO u ws 51 504485002 2/11/2020 Co-58 -5.66E-01 6.92E-Ol 2.IOE+OO u ws 51 504485002 2/1112020 Co-60 -1.86E+OO 8.67E-01 2.07E+OO u ws 51 504485002 2/11/2020 Cr-51 9.12E-01 7.28E+OO 2.30E+01 u ws 51 504485002 2/11/2020 Cs-134 -2.87E+OO 1.42E+OO 2.38E+OO u ws 51 504485002 2/1 J/2020 Cs- 13 7 -1.IOE+OO 7.91E-01 2.31E+OO u ws 51 504485002 2/11/2020 Fe-59 -4.02E+OO 1.75E+OO 4.24E+OO u ws 51 504485002 2/11/2020 1-131 -4.89E-01 1.52E+OO 4.67E+OO u ws 51 504485002 2/11/2020 K-40 3.17E+02 3.12E+01 2.52E+Ol ws 51 504485002 2/11 /2020 La-140 -3.55E-01 1.53E+OO 4.95E+OO u ws 51 504485002 2/11/2020 Mn-54 -2.81E-02 6.79E-01 1.96E+OO u ws 51 504485002 2/11 /2020 Nb-95 1.69E-02 6.77E-01 2.21E+OO u ws 51 504485002 2/11/2020 Pb-212 -2.73E+OO 2.19E+OO 4.85E+OO u ws 51 504485002 2/11/2020 Pb-214 -5.76E+OO 3.82E+OO 5.98E+OO u ws 51 504485002 2/11 /2020 Ru-I 03 -5.63E-01 8.14E-01 2.36E+OO u ws 51 504485002 2/11/2020 Ru-I 06 6.26E+OO 6.18E+OO 2.08E+01 u ws 51 504485002 2/11 /2020 Sb-124 8.27E-01 1.66E+OO 5.64E+OO u ws 51 504485002 2/11/2020 Sb-125 2.43E+OO 1.81E+OO 6.1 IE+OO u ws 51 504485002 2/11 /2020 Se-75 4.00E-01 l.31E+OO 3.06E+OO u ws 51 504485002 2/11/2020 Th-228 -2.73E+OO 2.19E+OO 4.85E+OO u ws 51 504485002 2/11/2020 Zn-65 -2.06E+OO 1.71E+OO 4.42E+OO u ws 51 504485002 2/1112020 Zr-95 6.41E-01 1.29E+OO 4.29E+OO u ws 51 507593002 3/18/2020 Ac-228 6.58E-Ol 3.93E+OO 1.02E+Ol u ws 51 507593002 3/18/2020 Ag-108m -1.34E-01 5.40E-01 1.71E+OO u ws 51 507593002 3/18/2020 Ag-I I Om 3.92E-01 7.98E-01 2.66E+OO u ws 51 507593002 3/18/2020 Ba-140 -3.62E+OO 2.95E+OO 9.16E+OO u 250

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/L) (pCi/ L) (pCi/ L) ws 51 507593002 3/18/2020 Be-7 2.36E+OO 5.13E+OO l.65E+Ol u ws 51 507593002 3/18/2020 Bi-214 -8.34E-Ol 2.47E+OO 5.14E+OO u ws 51 507593002 3/18/2020 Ce-141 -5.14E+OO 2.06E+OO 3.59E+OO u ws 51 507593002 3/18/2020 Ce-144 -l.66E+OO 3.90E+OO 1.32E+Ol u ws 51 507593002 3/18/2020 Co-57 -4.32E-01 5.15E-01 l.70E+OO u ws 51 507593002 3/18/2020 Co-58 3.52E-01 6.3IE-Ol 2.1 IE+OO u ws 51 507593002 3/18/2020 Co-60 1.40E+OO 7.52E-01 2.49E+OO u ws 51 507593002 3/18/2020 Cr-51 -3.70E+OO 5.88E+OO l.87E+Ol u ws 51 507593002 3/18/2020 Cs-134 8.83E-01 7.03E-Ol 2.34E+OO u ws 51 507593002 3/18/2020 Cs-137 -3.48E-01 6.04E-01 l.96E+OO u ws 51 507593002 3/18/2020 Fe-59 2.17E+OO 2.84E+OO 4.62E+OO u ws 51 507593002 3/18/2020 I-131 -1.38E+OO 1.15E+OO 3.45E+OO u ws 51 507593002 3/18/2020 K-40 3.09E+02 2.75E+Ol 2.15E+Ol ws 51 507593002 3/18/2020 La-140 -1.32E+OO l.02E+OO 2.94E+OO u ws 51 507593002 3/18/2020 Mn-54 3.20E-02 5.86E-01 l.93E+OO u ws 51 507593002 3/18/2020 Nb-95 l.77E-01 6.47E-01 2.16E+OO u ws 51 507593002 3/18/2020 Pb-212 -4.60E+OO 2.46E+OO 4.65E+OO u ws 51 507593002 3/18/2020 Pb-214 -l.60E+OO 2.58E+OO 4.88E+OO u ws 51 507593002 3/18/2020 Ru-103 8.05E-01 7.81E-01 l.83E+OO u ws 51 507593002 3/18/2020 Ru-106 2.39E+OO 5.21E+OO l.77E+Ol u ws 51 507593002 3/18/2020 Sb-124 3.83E-01 l.73E+OO 5.02E+OO u ws 51 507593002 3/18/2020 Sb-125 8.6IE-01 l.64E+OO 5.32E+OO u ws 51 507593002 3/18/2020 Se-75 1.IIE+OO 8.30E-01 2.69E+OO u ws 51 507593002 3/18/2020 Th-228 -4.60E+OO 2.46E+OO 4.65E+OO u ws 51 507593002 3/18/2020 Zn-65 -4.35E-Ol l.45E+OO 3.97E+OO u ws 51 507593002 3/18/2020 Zr-95 7.53E-01 l.08E+OO 3.64E+OO u ws 51 510624002 3/18/2020 H-3 1.33E+02 l.13E+02 3.54E+02 u ws 51 509885002 4/16/2020 Ac-228 6.38E-Ol 3.34E+OO 6.91E+OO u ws 51 509885002 4/16/2020 Ag-108m -1.17E-01 4.27E-01 1.40E+OO u ws 51 509885002 4/16/2020 Ag-11 Om -3.44E-01 6.02E-01 1.82E+OO u ws 51 509885002 4/16/2020 Ba-140 1.34E+OO 2.25E+OO 7.41E+OO u ws 51 509885002 4116/2020 Be-7 -5.55E+OO 4.19E+OO l.26E+Ol u ws 51 509885002 4/16/2020 Bi-214 O.OOE+OO 2.12E+OO 3.66E+OO u ws 51 509885002 4116/2020 Ce-141 -4.28E+OO l.75E+OO 2.74E+OO u ws 51 509885002 4/16/2020 Ce-144 l.03E+OO 3.22E+OO l.04E+Ol u ws 51 509885002 4/16/2020 Co-57 -5.53E-01 4.46E-01 1.35E+OO u ws 51 509885002 4/16/2020 Co-58 -5.13E-01 4.30E-01 1.34E+OO u ws 51 509885002 4/16/2020 Co-60 l.53E-Ol 5.0IE-01 l.66E+OO u ws 51 509885002 4/16/2020 Cr-51 3.04E-01 4.24E+OO l.44E+Ol u ws 51 509885002 4/16/2020 Cs-134 8.87E-01 7.30E-01 l.62E+OO u ws 51 509885002 4116/2020 Cs-137 3.47E-01 5.05E-Ol l.64E+OO u ws 51 509885002 4116/2020 Fe-59 1.34E+OO l.02E+OO 3.40E+OO u ws 51 509885002 4/16/2020 1-131 -9.97E-01 8.17E-01 2.54E+OO u ws 51 509885002 4/16/2020 K-40 2.78E+02 2.40E+Ol l.54E+Ol ws 51 509885002 4/16/2020 La-140 -2.95E-01 8.49E-01 2.66E+OO u ws 51 509885002 4/16/2020 Mn-54 -7.87E-01 6.81E-01 l.48E+OO u ws 51 509885002 4116/2020 Nb-95 4.62E-01 4.98E-01 l.60E+OO u ws 51 509885002 4/16/2020 Pb-212 O.OOE+OO 2.39E+OO 3.45E+OO u ws 51 509885002 4/16/2020 Pb-214 -1.97E+OO l.88E+OO 3.62E+OO u 251

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/L) (pCi/ L) (pCi/ L) ws 51 509885002 4/16/2020 Ru-103 3. l IE-01 5.23E-Ol

l.56E+OO u ws 51

509885002 4/16/2020 Ru-106 -2.90E+OO 4.67E+OO l.29E+Ol u ws 51 509885002 4/16/2020 Sb-124 O.OOE+OO O.OOE+OO 3.67E+OO u ws 51 509885002 4/16/2020 Sb-125 -2.09E+OO l.34E+OO 3.95E+OO u ws 51 509885002 4/16/2020 Se-75 4.94E-Ol 6.25E-Ol 2.13E+OO u ws 51 509885002 4/16/2020 Th-228 O.OOE+OO 2.39E+OO 3.45E+OO u ws 51 509885002 4/16/2020 Zn-65 -l.63E+OO l.06E+OO 3.03E+OO u ws 51 509885002 4/16/2020 Zr-95 -8.84E-Ol 8.55E-Ol 2.51E+OO u ws 51 511584002 5/14/2020 Ac-228 2.47E+OO 3.49E+OO 5.32E+OO u ws 51 511584002 5/14/2020 Ag-108m 5.23E-Ol 4.03E-Ol l.33E+OO u ws 51 511584002 5/14/2020 Ag-1 lOm l.93E-01 5.95E-01 2.04E+OO u ws 51 511584002 5/14/2020 Ba-140 l.95E+OO 2.47E+OO 8.19E+OO u ws 51 511584002 5/14/2020 Be-7 2.25E+OO 3.92E+OO 1.31E+Ol u ws 51 511584002 5/14/2020 Bi-214 O.OOE+OO 3.08E+OO 3.64E+OO u ws 51 511584002 5/14/2020 Ce-141 O.OOE+OO l.63E+OO 2.54E+OO u ws 51 511584002 5/14/2020 Ce-144 7.48E-01 2.95E+OO 9.65E+OO u ws 51 511584002 5/14/2020 Co-57 -2.20E-01 3.95E-01 l.27E+OO u ws 51 511584002 5/14/2020 Co-58 -3.85E-Ol 4.72E-Ol 1.42E+OO u ws 51 511584002 5/14/2020 Co-60 -l.96E-01 5.65E-Ol l.58E+OO u ws 51 511584002 5/14/2020 Cr-51 -2.15E+OO 4.02E+OO l.34E+Ol u ws 51 511584002 5/14/2020 Cs-134 -9.71E-02 5.15E-01 1.63E+OO u ws 51 511584002 5/14/2020 Cs-137 -6.96E-Ol 9.08E-Ol l.86E+OO u ws 51 511584002 5/14/2020 Fe-59 -9.30E-Ol l.lOE+OO 3.02E+OO u ws 51 511584002 5/14/2020 I-131 2.63E-Ol 8.36E-Ol 2.85E+OO u ws 51 511584002 5/14/2020 K-40 2.84E+02 2.41E+Ol l.54E+Ol ws 51 511584002 5/14/2020 La-140 -l.62E-Ol 7.91E-01 2.52E+OO u ws 51 511584002 5/14/2020 Mn-54 -5.48E-Ol 4.54E-Ol l.31E+OO u ws 51 511584002 5/14/2020 Nb-95 -3.47E-01 4.98E-Ol l.53E+OO u ws 51 511584002 5/14/2020 Pb-212 l.99E-01 l.78E+OO 3.41E+OO u ws 51 511584002 5/14/2020 Pb-214 -l.23E+OO l.54E+OO 3.51E+OO u ws 51 511584002 5/14/2020 Ru-103 5.20E-Ol 5.43E-Ol l.63E+OO u ws 51 511584002 5/14/2020 Ru-106 3.28E+OO 3.87E+OO l.27E+Ol u ws 51 511584002 5/14/2020 Sb-124 2.39E+OO l.24E+OO 4.03E+OO u ws 51 511584002 5/14/2020 Sb-125 2.88E+OO l.71E+OO 3.84E+OO u ws 51 511584002 5/14/2020 Se-75 3.29E-Ol 6.49E-01 2.04E+OO u ws 51 511584002 5/14/2020 Th-228 l.99E-Ol l.78E+OO 3.41E+OO u ws 51 511584002 5/14/2020 Zn-65 -3.73E-Ol 8.87E-Ol 2.89E+OO u ws 51 511584002 5/14/2020 Zr-95 l.47E+OO 1.1 IE+OO 2.68E+OO u ws 51 514167002 6/17/2020 Ac-228 -5.84E+OO 4.37E+OO 8.05E+OO u ws 51 514167002 6/17/2020 Ag-108m -l.59E-01 4.16E-01 l.37E+OO u ws 51 514167002 6/17/2020 Ag-llOm -2.68E-01 6.74E-01 2.24E+OO u ws 51 514167002 6/17/2020 Ba-140 -9.71E-Ol 2.28E+OO 7.34E+OO u ws 51 514167002 6/17/2020 Be-7 5.09E+OO 4.34E+OO l.44E+Ol u ws 51 514167002 6/17/2020 Bi-214 O.OOE+OO 2.80E+OO 3.44E+OO u ws 51 514167002 6/17/2020 Ce-141 3.06E-Ol 8.58E-Ol 2.80E+OO u ws 51 514167002 6/17/2020 Ce-144 l.38E+OO 3.20E+OO l.05E+Ol u ws 51 514167002 6/17/2020 Co-57 3.37E-02 4.06E-Ol l .34E+OO u ws 51 514167002 6/17/2020 Co-58 7.58E-03 5.llE-01 l.62E+OO u ws 51 514167002 6/17/2020 Co-60 7.50E-Ol 6.27E-Ol 2.09E+OO u 252

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/L) (pCi/ L) (pCi/ L) ws 51 514167002 6/17 /2020 Cr-51 -2.06E+OO 4.43E+OO 1.49E+Ol u ws 51 514167002 6117/2020 Cs-134 -2.72E-01 5.95E-01 1.74E+OO u ws 51 514167002 6/17/2020 Cs-137 1.1 lE-01 5.53E-01 1.80E+OO u ws 51 514167002 6/17/2020 Fe-59 -5.22E-01 1.18E+OO 3.83E+OO u ws 51 514167002 6/17/2020 I-131 3.92E-01 8.04E-01 2.73E+OO u ws 51 514167002 6/17/2020 K-40 3.16E+02 2.42E+Ol 1.47E+Ol ws 51 514167002 6/17/2020 La-140 1.48E-01 9.21E-01 2.98E+OO u ws 51 514167002 6/17/2020 Mn-54 -2.98E-01 5.0lE-01 1.65E+OO u ws 51 514167002 6/17/2020 Nb-95 5.66E-02 6.12E-01 1.74E+OO u ws 51 514167002 6/17/2020 Pb-212 O.OOE+OO l.86E+OO 2.94E+OO u ws 51 514167002 6/17/2020 Pb-214 2.81E+OO 2.15E+OO 3.67E+OO u ws 51 514167002 6/17/2020 Ru-103 -6.56E-01 5.35E-01 1.62E+OO u ws 51 514167002 6/17/2020 Ru-106 9.68E+OO 5.05E+OO 1.58E+Ol u ws 51 514167002 6/17/2020 Sb-124 -1.65E+OO 1.43E+OO 4.33E+OO u ws 51 514167002 6/17/2020 Sb-125 l.08E+OO l.42E+OO 4.33E+OO u ws 51 514167002 6/17/2020 Se-75 5.66E-01 6.93E-01 2.17E+OO u ws 51 514167002 6/17/2020 Th-228 O.OOE+OO 1.86E+OO 2.94E+OO u ws 51 514167002 6/17/2020 Zn-65 4.72E-01 1.29E+OO 3.84E+OO u ws 51 514167002 6/17/2020 Zr-95 3.67E-01 8.39E-01 2.72E+OO u ws 51 517017002 6/17/2020 H-3 -3.80E+Ol 1.41E+02 4.69E+02 u ws 51 516195002 7/15/2020 Ac-228 6.19E+OO 5.30E+OO 9.37E+OO u ws 51 516195002 7/15/2020 Ag-108m -4.75E-01 5.26E-01 1.66E+OO u ws 51 516195002 7/15/2020 Ag-llOm -l.37E+OO 8.30E-01 2.37E+OO u ws 51 516195002 7/15/2020 Ba-140 3.43E+OO 3.14E+OO l.04E+Ol u ws 51 516195002 7/15/2020 Be-7 -3.23E+OO 5.1 lE+OO 1.64E+Ol u ws 51 516195002 7/15/2020 Bi-214 -l.38E+OO l.97E+OO 4.29E+OO u ws 51 516195002 7115/2020 Ce-141 O.OOE+OO 1.63E+OO 3.38E+OO u ws 51 516195002 7/15/2020 Ce-144 -6.36E+OO 4.19E+OO 1.23E+Ol u ws 51 516195002 7/15/2020 Co-57 3.46E-01 5.lOE-01 1.67E+OO u ws 51 516195002 7/15/2020 Co-58 -1.85E-01 6.75E-01 2.lOE+OO u ws 51 516195002 7/15/2020 Co-60 1.67E+OO 7.19E-01 2.29E+OO u ws 51 516195002 7/15/2020 Cr-51 9.88E+OO 5.75E+OO 1.88E+Ol u ws 51 516195002 7/15/2020 Cs-134 1.26E+OO 7.54E-01 2.39E+OO u ws 51 516195002 7/15/2020 Cs-137 -5.37E-01 6.64E-01 2.03E+OO u ws 51 516195002 7/15/2020 Fe-59 3.35E+OO l.65E+OO 5.28E+OO u ws 51 516195002 7/15/2020 1-131 -2.65E-01 1.03E+OO 3.44E+OO u ws 51 516195002 7/15/2020 K-40 3.17E+02 2.96E+Ol 2.45E+Ol ws 51 516195002 7/15/2020 La-140 -1.07E+OO l.33E+OO 3.36E+OO u ws 51 516195002 7/15/2020 Mn-54 -3.00E-01 5.71E-01 l.88E+OO u ws 51 516195002 7/15/2020 Nb-95 -2.96E-01 6.72E-01 1.97E+OO u ws 51 516195002 7/15/2020 Pb-212 O.OOE+OO 2.46E+OO 4.35E+OO u ws 51 516195002 7/15/2020 Pb-214 -2.14E+OO l.91E+OO 4.57E+OO u ws 51 516195002 7/15/2020 Ru-103 -l.34E+OO 7.19E-01 1.98E+OO u ws 51 516195002 7/15/2020 Ru-106 6.33E+OO 5.76E+OO 1.71E+Ol u ws 51 516195002 7/15/2020 Sb-124 -2.62E-01 l.49E+OO 4.96E+OO u ws 51 516195002 7/15/2020 Sb-125 2.62E-01 1.50E+OO 5.03E+OO u ws 51 516195002 7/15/2020 Se-75 -3.78E-02 8.06E-01 2.50E+OO u ws 51 516195002 7/15/2020 Th-228 O.OOE+OO 2.46E+OO 4.35E+OO u ws 51 516195002 7/15/2020 Zn-65 1.29E+OO l.37E+OO 4.63E+OO u 253

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/L) (pCi/ L) (pCi/ L) ws 51 516195002 7/15/2020 Zr-95 l.13E+OO l.15E+OO 3.73E+OO u ws 51 518708002 8/11/2020 Ac-228 l.OIE+Ol 8.45E+OO l.56E+Ol u ws 51 518708002 8/11/2020 Ag-108m -2.89E-02 7.13E-Ol 2.29E+OO u ws 51 518708002 8/11/2020 Ag-l!Om -5.03E-Ol l.25E+OO 3.97E+OO u ws 51 518708002 8/11/2020 Ba-140 4.64E-Ol 4.23E+OO l.35E+Ol u 254

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/L) (pCi/ L) (pCi/L) ws 51 518708002 8/11/2020 Be-7 -l.l8E+Ol 8.68E+OO 2.42E+Ol u ws 51 518708002 8/11/2020 Bi-214 l.OIE+Ol 4.06E+OO 5.60E+OO ws 51 518708002 8/11/2020 Ce-141 -l.72E+OO l.68E+OO 4.79E+OO u ws 51 518708002 8/11/2020 Ce-144 l.03E+Ol 6.24E+OO 2.07E+Ol u ws 51 518708002 8/ll/2020 Co-57 l.l5E-01 7.29E-Ol 2.51E+OO u ws 51 518708002 8/11/2020 Co-58 -6.06E-Ol 8.91E-Ol 2.78E+OO u ws 51 518708002 8/11/2020 Co-60 7.82E-Ol l.OOE+OO 3.28E+OO u ws 51 518708002 8/11/2020 Cr-51 4.94E+OO 8.36E+OO 2.78E+Ol u ws 51 518708002 8/11/2020 Cs-134 l.53E-Ol 8.48E-Ol 2.85E+OO u ws 51 518708002 8/11/2020 Cs-137 6.06E-01 8.68E-Ol 3.00E+OO u ws 51 518708002 8/11/2020 Fe-59 l.l4E+OO l.96E+OO 6.57E+OO u ws 51 518708002 8/11/2020 1-131 4.79E-Ol l.57E+OO 5.17E+OO u ws 51 518708002 8/ll/2020 K-40 3.36E+02 3.68E+Ol 3.55E+Ol DL ws 51 518708002 8/ll/2020 La-140 -3.48E+OO 2.18E+OO 4.95E+OO u ws 51 518708002 8/11/2020 Mn-54 -3.72E-Ol 8.89E-Ol 2.85E+OO u ws 51 518708002 8/11/2020 Nb-95 5.06E-03 9.47E-Ol 3.15E+OO u ws 51 518708002 8/ll/2020 Pb-212 2.86E+OO 3.06E+OO 5.34E+OO u ws 51 518708002 8/11/2020 Pb-214 -l.06E+OO 2.33E+OO 7.06E+OO u ws 51 518708002 8/11/2020 Ru-103 5.78E-Ol 9.40E-Ol 3.07E+OO u ws 51 518708002 8/11/2020 Ru-106 -7.02E+OO 8.56E+OO 2.72E+Ol u ws 51 518708002 8/11/2020 Sb-124 3.l5E+OO 2.42E+OO 8.56E+OO u ws 51 518708002 8/11/2020 Sb-125 4.69E-Ol 2.27E+OO 7.37E+OO u ws 51 518708002 8/11/2020 Se-75 -l.52E+OO l.22E+OO 3.66E+OO u ws 51 518708002 8/ll/2020 Th-228 2.86E+OO 3.06E+OO 5.34E+OO u ws 51 518708002 8/11/2020 Zn-65 O.OOE+OO 2.90E+OO 5.59E+OO u ws 51 518708002 8/11/2020 Zr-95 -5.30E-Ol l.57E+OO 5.llE+OO u ws 51 522263002 9/16/2020 Ac-228 O.OOE+OO 4.57E+OO 5.15E+OO u ws 51 522263002 9/16/2020 Ag-108m -5.49E-Ol 3.94E-Ol l.l5E+OO u ws 51 522263002 9/16/2020 Ag-1 lOm -6.95E-02 5.99E-Ol l.97E+OO u ws 51 522263002 9/16/2020 Ba-140 -3.20E-Ol 2.88E+OO 9.09E+OO u ws 51 522263002 9/16/2020 Be-7 3.l6E+OO 4.53E+OO l.30E+Ol u ws 51 522263002 9/16/2020 Bi-214 -9.67E-Ol 2.0lE+OO 3.62E+OO u ws 51 522263002 9/16/2020 Ce-141 -l.35E+OO 9.19E-01 2.88E+OO u ws 51 522263002 9/16/2020 Ce-144 7.50E-Ol 2.93E+OO l.OOE+Ol u ws 51 522263002 9/16/2020 Co-57 -2.l lE-01 3.97E-Ol l.34E+OO u ws 51 522263002 9/16/2020 Co-58 -2.78E-01 5.02£-01 l.41E+OO u ws 51 522263002 9/16/2020 Co-60 -l.23E-Ol 4.78E-Ol l.60E+OO u ws 51 522263002 9/16/2020 Cr-51 -6.27E-Ol 4.72E+OO l.54E+Ol u ws 51 522263002 9/16/2020 Cs-134 8.26E-Ol 5.05E-Ol l.63E+OO u ws 51 522263002 9/16/2020 Cs-137 -l.l2E+OO 4.97E-Ol l.30E+OO u ws 51 522263002 9/16/2020 Fe-59 8.99E-01 l.08E+OO 3.53E+OO u ws 51 522263002 9/16/2020 I-131 2.53E+OO l.42E+OO 4.38E+OO u ws 51 522263002 9/16/2020 K-40 3.44E+02 2.51E+Ol l.49E+Ol ws 51 522263002 9/16/2020 La-140 -l.56E+OO l.07E+OO 3.l2E+OO u ws 51 522263002 9/16/2020 Mn-54 l.08E-Ol 4.30E-Ol l.43E+OO u ws 51 522263002 9/16/2020 Nb-95 8.0lE-02 8.29E-Ol l.63E+OO u ws 51 522263002 9/16/2020 Pb-212 -l.l9E+OO l.91E+OO 3.38E+OO u ws 51 522263002 9/16/2020 Pb-214 6.54E-03 2.lOE+OO 3.72E+OO u ws 51 522263002 9/16/2020 Ru-103 -5.41E-02 6.58£-01 l.45E+OO u ws 51 522263002 9/16/2020 Ru-106 -2.06E+OO 3.98E+OO l.32E+Ol u 255

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/L) (pCi/L) (pCi/L) ws 51 522263002 9/16/2020 Sb-124 4.12E-01 1.25E+OO 4.17E+OO u ws 51 522263002 9/16/2020 Sb-125 -2.46E-01 1.27E+OO 3.61E+OO u ws 51 522263002 9/16/2020 Se-75 8.23E-01 6.49E-01 2.lOE+OO u ws 51 522263002 9/16/2020 Th-228 -1.19E+OO 1.91E+OO 3.38E+OO u ws 51 522263002 9/16/2020 Zn-65 1.15E+OO l.lOE+OO 3.59E+OO u ws 51 522263002 9/16/2020 Zr-95 -2.47E+OO 1.02E+OO 2.53E+OO u ws 51 526424002 9/16/2020 H-3 -1.84E+02 1.57E+02 5.46E+02 u ws 51 524955002 10/15/2020 Ac-228 -8.76E-01 3.04E+OO 6.13E+OO u ws 51 524955002 10/15/2020 Ag-108m -1.81E-01 3.61E-01 1.06E+OO u ws 51 524955002 10/15/2020 Ag-llOm 1.33E-01 5.lOE-01 1.66E+OO u ws 51 524955002 10/15/2020 Ba-140 -8.61E-02 2.55E+OO 8.48E+OO u ws 51 524955002 10/15/2020 Be-7 -1.54E+OO 3.61E+OO 1.19E+Ol u ws 51 524955002 10/15/2020 Bi-214 O.OOE+OO 2.22E+OO 2.63E+OO u ws 51 524955002 10/15/2020 Ce-141 7.19E-01 8.05E-01 2.39E+OO u ws 51 524955002 10/15/2020 Ce-144 -1.80E+OO 2.73E+OO 8.58E+OO u ws 51 524955002 10/15/2020 Co-57 2.1 lE-01 3.43E-01 1.llE+OO u ws 51 524955002 10/15/2020 Co-58 -1.89E-01 4.04E-01 1.27E+OO u ws 51 524955002 10/15/2020 Co-60 5.1 lE-01 4.18E-01 l.43E+OO u ws 51 524955002 10/15/2020 Cr-51 2.78E+OO 4.07E+OO 1.40E+Ol u ws 51 524955002 10/15/2020 Cs-134 -1.07E-01 4.32E-01 1.38E+OO u ws 51 524955002 10/15/2020 Cs-137 -l.19E+OO 5.15E-01 1.19E+OO u ws 51 524955002 10/15/2020 Fe-59 -3.69E-01 9.22E-01 2.85E+OO u ws 51 524955002 10/15/2020 1-131 -2.49E+OO 1.16E+OO 3.19E+OO u ws 51 524955002 10/15/2020 K-40 3.34E+02 2.20E+Ol 1.17E+Ol ws 51 524955002 10/15/2020 La-140 5.02E-01 8.12E-01 2.76E+OO u ws 51 524955002 10/15/2020 Mn-54 1.32E-01 3.97E-01 1.30E+OO u ws 51 524955002 10/15/2020 Nb-95 5.28E-01 4.27E-01 1.40E+OO u ws 51 524955002 10/15/2020 Pb-212 2.27E+OO 1.87E+OO 3.19E+OO u ws 51 524955002 10/15/2020 Pb-214 -5.81E-01 1.57E+OO 3.33E+OO u ws 51 524955002 10/15/2020 Ru-103 -5.38E-01 8.39E-01 1.46E+OO u ws 51 524955002 10/15/2020 Ru-106 9.97E-01 3.59E+OO 1.19E+Ol u ws 51 524955002 10/15/2020 Sb-124 -9.43E-01 9.77E-01 2.93E+OO u ws 51 524955002 10/15/2020 Sb-125 -6.09E-01 l.27E+OO 2.93E+OO u ws 51 524955002 10/15/2020 Se-75 5.97E-01 5.62E-01 1.75E+OO u ws 51 524955002 10/15/2020 Th-228 2.27E+OO 1.87E+OO 3.19E+OO u ws 51 524955002 10/15/2020 Zn-65 4.98E-01 9.25E-01 2.85E+OO u ws 51 524955002 10/15/2020 Zr-95 -1.47E+OO 7.80E-01 2.06E+OO u ws 51 528806002 11/18/2020 Ac-228 -2.92E+OO 3.69E+OO 6.73E+OO u ws 51 528806002 11118/2020 Ag-108m -3.44E-01 4.44E-01 1.26E+OO u ws 51 528806002 11/18/2020 Ag-llOm 2.25E-02 6.13E-01 1.98E+OO u ws 51 528806002 11/18/2020 Ba-140 -3.02E-01 3.04E+OO 9.96E+OO u ws 51 528806002 11/18/2020 Be-7 5.31E+OO 4.13E+OO 1.35E+Ol u ws 51 528806002 11/18/2020 Bi-214 -2.33E+OO l.99E+OO 3.49E+OO u ws 51 528806002 11/18/2020 Ce-141 1.64E+OO 1.13E+OO 3.34E+OO u ws 51 528806002 11/18/2020 Ce-144 1.57E+OO 3.23E+OO 1.lOE+Ol u ws 51 528806002 11/18/2020 Co-57 2.26E-01 4.27E-01 1.45E+OO u ws 51 528806002 11118/2020 Co-58 -3.50E-01 5.19E-01 1.43E+OO u 256

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/L) (pCi/L) (pCi/ L) ws 51 528806002 11118/2020 Co-60 5.70E-Ol 5.33E-Ol l.72E+OO u ws 51 528806002 11118/2020 Cr-51 -3.55E-Ol 5.05E+OO l.68E+Ol u ws 51 528806002 11118/2020 Cs-134 l.38E-Ol 5.51E-Ol l.61E+OO u ws 51 528806002 11/18/2020 Cs-13 7 3.57E-01 4.87E-Ol 1.60E+OO u ws 51 528806002 11118/2020 Fe-59 -1.IIE+OO l.14E+OO 3.41E+OO u ws 51 528806002 11118/2020 1-131 -4.43E-Ol 3.13E+OO 4.42E+OO u ws 51 528806002 11118/2020 K-40 3.25E+02 2.56E+Ol l.43E+Ol ws 51 528806002 11118/2020 La-140 -7.67E-Ol 9.43E-Ol 2.99E+OO u ws 51 528806002 11118/2020 Mn-54 3.54E-Ol 4.59E-Ol l.50E+OO u ws 51 528806002 11118/2020 Nb-95 -l.12E-Ol 5.15E-Ol l.66E+OO u ws 51 528806002 11118/2020 Pb-212 2.31E+OO 2.18E+OO 3.54E+OO u ws 51 528806002 11/18/2020 Pb-214 -4.57E+OO 2.27E+OO 3.68E+OO u ws 51 528806002 11/18/2020 Ru-I 03 -l.28E-Ol 6.92E-Ol l.59E+OO u ws 51 528806002 11/18/2020 Ru-106 -6.27E+OO 4.18E+OO l.21E+Ol u ws 51 528806002 11/18/2020 Sb-124 1.74E+OO l.18E+OO 4.02E+OO u ws 51 528806002 11118/2020 Sb-125 -2.34E-Ol l.20E+OO 3.95E+OO u ws 51 528806002 11/18/2020 Se-75 2.15E-Ol 6.22E-Ol 2.09E+OO u ws 51 528806002 11/18/2020 Th-228 2.31E+OO 2.18E+OO 3.54E+OO u ws 51 528806002 11118/2020 Zn-65 -4.50E-Ol l.04E+OO 3.24E+OO u ws 51 528806002 11/18/2020 Zr-95 8.36E-02 8.78E-Ol 2.86E+OO u ws 51 530337002 12/9/2020 Ac-228 I.98E+OO l.77E+OO 5.77E+OO u ws 51 530337002 12/9/2020 Ag-108m -4.93E-Ol 3.58E-Ol 1.IOE+OO u ws 51 530337002 12/9/2020 Ag-1 lOm -l.26E-Ol 5.56E-Ol l.77E+OO u ws 51 530337002 12/9/2020 Ba-140 4.00E+OO 2.90E+OO 9.28E+OO u ws 51 530337002 12/9/2020 Be-7 -2.35E+OO 3.46E+OO l.13E+Ol u ws 51 530337002 12/9/2020 Bi-214 1.79E+OO 2.34E+OO 2.71E+OO u ws 51 530337002 12/9/2020 Ce-141 9.96E-02 7.48E-Ol 2.46E+OO u ws 51 530337002 12/9/2020 Ce-144 -7.61E-Ol 2.52E+OO 8.22E+OO u ws 51 530337002 12/9/2020 Co-57 2.87E-Ol 3.28E-Ol l.08E+OO u ws 51 530337002 12/9/2020 Co-58 -2.16E-Ol 3.94E-Ol l.23E+OO u ws 51 530337002 12/9/2020 Co-60 7.35E-Ol 4.28E-Ol 1.44E+OO u ws 51 530337002 12/9/2020 Cr-51 -5.66E+OO 4.64E+OO 1.34E+Ol u ws 51 530337002 12/9/2020 Cs-134 -3.75E-01 7.58E-Ol l.48E+OO u ws 51 530337002 12/9/2020 Cs-137 -2.48E-Ol 4.18E-Ol 1.33E+OO u ws 51 530337002 12/9/2020 Fe-59 -8.02E-Ol 9.94E-Ol 2.96E+OO u ws 51 530337002 12/9/2020 1-131 -2.08E-Ol l.15E+OO 3.94E+OO u ws 51 530337002 12/9/2020 K-40 2.77E+02 2.03E+Ol l.46E+Ol ws 51 530337002 12/9/2020 La-140 -5.80E-Ol l.02E+OO 3.25E+OO u ws 51 530337002 12/9/2020 Mn-54 2.44E-Ol 4.09E-Ol 1.35E+OO u ws 51 530337002 12/9/2020 Nb-95 -9.18E-02 5.32E-Ol l.53E+OO u ws 51 530337002 12/9/2020 Pb-212 9.0IE-01 l.55E+OO 4.16E+OO u ws 51 530337002 12/9/2020 Pb-214 1.49E+OO l.93E+OO 3.37E+OO u ws 51 530337002 12/9/2020 Ru-103 -3.34E-Ol 5.02E-Ol l.46E+OO u ws 51 530337002 12/9/2020 Ru-106 -l.83E+OO 3.53E+OO 1.14E+Ol u ws 51 530337002 12/9/2020 Sb-124 -7.22E-Ol 9.6IE-Ol 2.94E+OO u ws 51 530337002 12/9/2020 Sb-125 2.53E-Ol l.OIE+OO 3.44E+OO u ws 51 530337002 12/9/2020 Se-75 l.71E+OO 9.0IE-01 l.83E+OO u ws 51 530337002 12/9/2020 Th-228 9.0IE-01 l.55E+OO 4.16E+OO u ws 51 530337002 12/9/2020 Zn-65 4.82E-01 9.00E-01 2.77E+OO u ws 51 530337002 12/9/2020 Zr-95 -7.03E-Ol 7.79E-Ol 2.39E+OO u 257

Seabrook REMP Summary of 2020 Data SAMPLE END CONC STD.DEV. MDC FLAGS TYPE STATION LSN DATE NUCLIDE (pCi/L) (pCi/L) (pCi/ L) ws 51 533258002 12/9/2020 H-3 1.38E+02 1.08E+02 3.38E+02 u FLAGS A blank Flag field indicates that the measured activity is considered positive as it is greater than the MDC and has no other qualifiers noted.

U: Target isotope was analyzed for but not detected above the MDC and LLD.

UI: Uncertain identification for gamma spectroscopy.

X: Lab-specific qualifier:

(1) False positive due to the presence of radon gas in the water.

M: Reported result is less than the LLD and greater than the MDC.

DL: Measured MDC is greater than the LLD.

DL*: Near miss of MDC being within round-off difference of being greater than the LLD.

258

SBK-L-21044, 2020 Annual Radiological Environmental Operating Report

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SBK-L-21044, 2020 Annual Radiological Environmental Operating Report

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